| Step | Hyp | Ref | Expression | 
						
							| 1 |  | remulcl |  |-  ( ( A e. RR /\ B e. RR ) -> ( A x. B ) e. RR ) | 
						
							| 2 | 1 | ad5antlr |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( A x. B ) e. RR ) | 
						
							| 3 |  | simprl |  |-  ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) -> a e. ZZ ) | 
						
							| 4 | 3 | ad3antrrr |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> a e. ZZ ) | 
						
							| 5 |  | simplrl |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> c e. ZZ ) | 
						
							| 6 | 4 5 | zmulcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( a x. c ) e. ZZ ) | 
						
							| 7 |  | eldifi |  |-  ( D e. ( NN \ []NN ) -> D e. NN ) | 
						
							| 8 | 7 | ad2antrr |  |-  ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) -> D e. NN ) | 
						
							| 9 | 8 | nnzd |  |-  ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) -> D e. ZZ ) | 
						
							| 10 | 9 | ad3antrrr |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> D e. ZZ ) | 
						
							| 11 |  | simplrr |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> d e. ZZ ) | 
						
							| 12 |  | simprr |  |-  ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) -> b e. ZZ ) | 
						
							| 13 | 12 | ad3antrrr |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> b e. ZZ ) | 
						
							| 14 | 11 13 | zmulcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( d x. b ) e. ZZ ) | 
						
							| 15 | 10 14 | zmulcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( D x. ( d x. b ) ) e. ZZ ) | 
						
							| 16 | 6 15 | zaddcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( a x. c ) + ( D x. ( d x. b ) ) ) e. ZZ ) | 
						
							| 17 | 4 11 | zmulcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( a x. d ) e. ZZ ) | 
						
							| 18 | 5 13 | zmulcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( c x. b ) e. ZZ ) | 
						
							| 19 | 17 18 | zaddcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( a x. d ) + ( c x. b ) ) e. ZZ ) | 
						
							| 20 |  | simprl |  |-  ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) -> A = ( a + ( ( sqrt ` D ) x. b ) ) ) | 
						
							| 21 | 20 | ad2antrr |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> A = ( a + ( ( sqrt ` D ) x. b ) ) ) | 
						
							| 22 |  | simprl |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> B = ( c + ( ( sqrt ` D ) x. d ) ) ) | 
						
							| 23 | 21 22 | oveq12d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( A x. B ) = ( ( a + ( ( sqrt ` D ) x. b ) ) x. ( c + ( ( sqrt ` D ) x. d ) ) ) ) | 
						
							| 24 |  | zcn |  |-  ( a e. ZZ -> a e. CC ) | 
						
							| 25 | 24 | ad2antrl |  |-  ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) -> a e. CC ) | 
						
							| 26 | 25 | ad3antrrr |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> a e. CC ) | 
						
							| 27 | 8 | nncnd |  |-  ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) -> D e. CC ) | 
						
							| 28 | 27 | ad3antrrr |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> D e. CC ) | 
						
							| 29 | 28 | sqrtcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( sqrt ` D ) e. CC ) | 
						
							| 30 |  | zcn |  |-  ( b e. ZZ -> b e. CC ) | 
						
							| 31 | 30 | ad2antll |  |-  ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) -> b e. CC ) | 
						
							| 32 | 31 | ad3antrrr |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> b e. CC ) | 
						
							| 33 | 29 32 | mulcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( sqrt ` D ) x. b ) e. CC ) | 
						
							| 34 |  | zcn |  |-  ( c e. ZZ -> c e. CC ) | 
						
							| 35 | 34 | adantr |  |-  ( ( c e. ZZ /\ d e. ZZ ) -> c e. CC ) | 
						
							| 36 | 35 | ad2antlr |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> c e. CC ) | 
						
							| 37 |  | zcn |  |-  ( d e. ZZ -> d e. CC ) | 
						
							| 38 | 37 | adantl |  |-  ( ( c e. ZZ /\ d e. ZZ ) -> d e. CC ) | 
						
							| 39 | 38 | ad2antlr |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> d e. CC ) | 
						
							| 40 | 29 39 | mulcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( sqrt ` D ) x. d ) e. CC ) | 
						
							| 41 | 26 33 36 40 | muladdd |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( a + ( ( sqrt ` D ) x. b ) ) x. ( c + ( ( sqrt ` D ) x. d ) ) ) = ( ( ( a x. c ) + ( ( ( sqrt ` D ) x. d ) x. ( ( sqrt ` D ) x. b ) ) ) + ( ( a x. ( ( sqrt ` D ) x. d ) ) + ( c x. ( ( sqrt ` D ) x. b ) ) ) ) ) | 
						
							| 42 | 29 39 29 32 | mul4d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( sqrt ` D ) x. d ) x. ( ( sqrt ` D ) x. b ) ) = ( ( ( sqrt ` D ) x. ( sqrt ` D ) ) x. ( d x. b ) ) ) | 
						
							| 43 | 28 | msqsqrtd |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( sqrt ` D ) x. ( sqrt ` D ) ) = D ) | 
						
							| 44 | 43 | oveq1d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( sqrt ` D ) x. ( sqrt ` D ) ) x. ( d x. b ) ) = ( D x. ( d x. b ) ) ) | 
						
							| 45 | 42 44 | eqtrd |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( sqrt ` D ) x. d ) x. ( ( sqrt ` D ) x. b ) ) = ( D x. ( d x. b ) ) ) | 
						
							| 46 | 45 | oveq2d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( a x. c ) + ( ( ( sqrt ` D ) x. d ) x. ( ( sqrt ` D ) x. b ) ) ) = ( ( a x. c ) + ( D x. ( d x. b ) ) ) ) | 
						
							| 47 | 26 29 39 | mul12d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( a x. ( ( sqrt ` D ) x. d ) ) = ( ( sqrt ` D ) x. ( a x. d ) ) ) | 
						
							| 48 | 36 29 32 | mul12d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( c x. ( ( sqrt ` D ) x. b ) ) = ( ( sqrt ` D ) x. ( c x. b ) ) ) | 
						
							| 49 | 47 48 | oveq12d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( a x. ( ( sqrt ` D ) x. d ) ) + ( c x. ( ( sqrt ` D ) x. b ) ) ) = ( ( ( sqrt ` D ) x. ( a x. d ) ) + ( ( sqrt ` D ) x. ( c x. b ) ) ) ) | 
						
							| 50 | 26 39 | mulcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( a x. d ) e. CC ) | 
						
							| 51 | 36 32 | mulcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( c x. b ) e. CC ) | 
						
							| 52 | 29 50 51 | adddid |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) = ( ( ( sqrt ` D ) x. ( a x. d ) ) + ( ( sqrt ` D ) x. ( c x. b ) ) ) ) | 
						
							| 53 | 49 52 | eqtr4d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( a x. ( ( sqrt ` D ) x. d ) ) + ( c x. ( ( sqrt ` D ) x. b ) ) ) = ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) | 
						
							| 54 | 46 53 | oveq12d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( a x. c ) + ( ( ( sqrt ` D ) x. d ) x. ( ( sqrt ` D ) x. b ) ) ) + ( ( a x. ( ( sqrt ` D ) x. d ) ) + ( c x. ( ( sqrt ` D ) x. b ) ) ) ) = ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) + ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) ) | 
						
							| 55 | 23 41 54 | 3eqtrd |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( A x. B ) = ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) + ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) ) | 
						
							| 56 | 50 51 | addcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( a x. d ) + ( c x. b ) ) e. CC ) | 
						
							| 57 | 29 56 | sqmuld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ^ 2 ) = ( ( ( sqrt ` D ) ^ 2 ) x. ( ( ( a x. d ) + ( c x. b ) ) ^ 2 ) ) ) | 
						
							| 58 | 28 | sqsqrtd |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( sqrt ` D ) ^ 2 ) = D ) | 
						
							| 59 | 58 | oveq1d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( sqrt ` D ) ^ 2 ) x. ( ( ( a x. d ) + ( c x. b ) ) ^ 2 ) ) = ( D x. ( ( ( a x. d ) + ( c x. b ) ) ^ 2 ) ) ) | 
						
							| 60 | 57 59 | eqtr2d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( D x. ( ( ( a x. d ) + ( c x. b ) ) ^ 2 ) ) = ( ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ^ 2 ) ) | 
						
							| 61 | 60 | oveq2d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) - ( D x. ( ( ( a x. d ) + ( c x. b ) ) ^ 2 ) ) ) = ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) - ( ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ^ 2 ) ) ) | 
						
							| 62 | 26 36 | mulcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( a x. c ) e. CC ) | 
						
							| 63 | 39 32 | mulcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( d x. b ) e. CC ) | 
						
							| 64 | 28 63 | mulcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( D x. ( d x. b ) ) e. CC ) | 
						
							| 65 | 62 64 | addcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( a x. c ) + ( D x. ( d x. b ) ) ) e. CC ) | 
						
							| 66 | 29 56 | mulcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) e. CC ) | 
						
							| 67 |  | subsq |  |-  ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) e. CC /\ ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) e. CC ) -> ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) - ( ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ^ 2 ) ) = ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) + ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) x. ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) - ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) ) ) | 
						
							| 68 | 65 66 67 | syl2anc |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) - ( ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ^ 2 ) ) = ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) + ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) x. ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) - ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) ) ) | 
						
							| 69 | 41 54 | eqtr2d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) + ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) = ( ( a + ( ( sqrt ` D ) x. b ) ) x. ( c + ( ( sqrt ` D ) x. d ) ) ) ) | 
						
							| 70 | 26 33 36 40 | mulsubd |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( a - ( ( sqrt ` D ) x. b ) ) x. ( c - ( ( sqrt ` D ) x. d ) ) ) = ( ( ( a x. c ) + ( ( ( sqrt ` D ) x. d ) x. ( ( sqrt ` D ) x. b ) ) ) - ( ( a x. ( ( sqrt ` D ) x. d ) ) + ( c x. ( ( sqrt ` D ) x. b ) ) ) ) ) | 
						
							| 71 | 46 53 | oveq12d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( a x. c ) + ( ( ( sqrt ` D ) x. d ) x. ( ( sqrt ` D ) x. b ) ) ) - ( ( a x. ( ( sqrt ` D ) x. d ) ) + ( c x. ( ( sqrt ` D ) x. b ) ) ) ) = ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) - ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) ) | 
						
							| 72 | 70 71 | eqtr2d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) - ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) = ( ( a - ( ( sqrt ` D ) x. b ) ) x. ( c - ( ( sqrt ` D ) x. d ) ) ) ) | 
						
							| 73 | 69 72 | oveq12d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) + ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) x. ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) - ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) ) = ( ( ( a + ( ( sqrt ` D ) x. b ) ) x. ( c + ( ( sqrt ` D ) x. d ) ) ) x. ( ( a - ( ( sqrt ` D ) x. b ) ) x. ( c - ( ( sqrt ` D ) x. d ) ) ) ) ) | 
						
							| 74 | 61 68 73 | 3eqtrd |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) - ( D x. ( ( ( a x. d ) + ( c x. b ) ) ^ 2 ) ) ) = ( ( ( a + ( ( sqrt ` D ) x. b ) ) x. ( c + ( ( sqrt ` D ) x. d ) ) ) x. ( ( a - ( ( sqrt ` D ) x. b ) ) x. ( c - ( ( sqrt ` D ) x. d ) ) ) ) ) | 
						
							| 75 | 26 33 | addcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( a + ( ( sqrt ` D ) x. b ) ) e. CC ) | 
						
							| 76 | 36 40 | addcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( c + ( ( sqrt ` D ) x. d ) ) e. CC ) | 
						
							| 77 | 26 33 | subcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( a - ( ( sqrt ` D ) x. b ) ) e. CC ) | 
						
							| 78 | 36 40 | subcld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( c - ( ( sqrt ` D ) x. d ) ) e. CC ) | 
						
							| 79 | 75 76 77 78 | mul4d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( a + ( ( sqrt ` D ) x. b ) ) x. ( c + ( ( sqrt ` D ) x. d ) ) ) x. ( ( a - ( ( sqrt ` D ) x. b ) ) x. ( c - ( ( sqrt ` D ) x. d ) ) ) ) = ( ( ( a + ( ( sqrt ` D ) x. b ) ) x. ( a - ( ( sqrt ` D ) x. b ) ) ) x. ( ( c + ( ( sqrt ` D ) x. d ) ) x. ( c - ( ( sqrt ` D ) x. d ) ) ) ) ) | 
						
							| 80 |  | subsq |  |-  ( ( a e. CC /\ ( ( sqrt ` D ) x. b ) e. CC ) -> ( ( a ^ 2 ) - ( ( ( sqrt ` D ) x. b ) ^ 2 ) ) = ( ( a + ( ( sqrt ` D ) x. b ) ) x. ( a - ( ( sqrt ` D ) x. b ) ) ) ) | 
						
							| 81 | 26 33 80 | syl2anc |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( a ^ 2 ) - ( ( ( sqrt ` D ) x. b ) ^ 2 ) ) = ( ( a + ( ( sqrt ` D ) x. b ) ) x. ( a - ( ( sqrt ` D ) x. b ) ) ) ) | 
						
							| 82 |  | subsq |  |-  ( ( c e. CC /\ ( ( sqrt ` D ) x. d ) e. CC ) -> ( ( c ^ 2 ) - ( ( ( sqrt ` D ) x. d ) ^ 2 ) ) = ( ( c + ( ( sqrt ` D ) x. d ) ) x. ( c - ( ( sqrt ` D ) x. d ) ) ) ) | 
						
							| 83 | 36 40 82 | syl2anc |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( c ^ 2 ) - ( ( ( sqrt ` D ) x. d ) ^ 2 ) ) = ( ( c + ( ( sqrt ` D ) x. d ) ) x. ( c - ( ( sqrt ` D ) x. d ) ) ) ) | 
						
							| 84 | 81 83 | oveq12d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( a ^ 2 ) - ( ( ( sqrt ` D ) x. b ) ^ 2 ) ) x. ( ( c ^ 2 ) - ( ( ( sqrt ` D ) x. d ) ^ 2 ) ) ) = ( ( ( a + ( ( sqrt ` D ) x. b ) ) x. ( a - ( ( sqrt ` D ) x. b ) ) ) x. ( ( c + ( ( sqrt ` D ) x. d ) ) x. ( c - ( ( sqrt ` D ) x. d ) ) ) ) ) | 
						
							| 85 | 29 32 | sqmuld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( sqrt ` D ) x. b ) ^ 2 ) = ( ( ( sqrt ` D ) ^ 2 ) x. ( b ^ 2 ) ) ) | 
						
							| 86 | 85 | oveq2d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( a ^ 2 ) - ( ( ( sqrt ` D ) x. b ) ^ 2 ) ) = ( ( a ^ 2 ) - ( ( ( sqrt ` D ) ^ 2 ) x. ( b ^ 2 ) ) ) ) | 
						
							| 87 | 29 39 | sqmuld |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( sqrt ` D ) x. d ) ^ 2 ) = ( ( ( sqrt ` D ) ^ 2 ) x. ( d ^ 2 ) ) ) | 
						
							| 88 | 87 | oveq2d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( c ^ 2 ) - ( ( ( sqrt ` D ) x. d ) ^ 2 ) ) = ( ( c ^ 2 ) - ( ( ( sqrt ` D ) ^ 2 ) x. ( d ^ 2 ) ) ) ) | 
						
							| 89 | 86 88 | oveq12d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( a ^ 2 ) - ( ( ( sqrt ` D ) x. b ) ^ 2 ) ) x. ( ( c ^ 2 ) - ( ( ( sqrt ` D ) x. d ) ^ 2 ) ) ) = ( ( ( a ^ 2 ) - ( ( ( sqrt ` D ) ^ 2 ) x. ( b ^ 2 ) ) ) x. ( ( c ^ 2 ) - ( ( ( sqrt ` D ) ^ 2 ) x. ( d ^ 2 ) ) ) ) ) | 
						
							| 90 | 79 84 89 | 3eqtr2d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( a + ( ( sqrt ` D ) x. b ) ) x. ( c + ( ( sqrt ` D ) x. d ) ) ) x. ( ( a - ( ( sqrt ` D ) x. b ) ) x. ( c - ( ( sqrt ` D ) x. d ) ) ) ) = ( ( ( a ^ 2 ) - ( ( ( sqrt ` D ) ^ 2 ) x. ( b ^ 2 ) ) ) x. ( ( c ^ 2 ) - ( ( ( sqrt ` D ) ^ 2 ) x. ( d ^ 2 ) ) ) ) ) | 
						
							| 91 | 58 | oveq1d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( sqrt ` D ) ^ 2 ) x. ( b ^ 2 ) ) = ( D x. ( b ^ 2 ) ) ) | 
						
							| 92 | 91 | oveq2d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( a ^ 2 ) - ( ( ( sqrt ` D ) ^ 2 ) x. ( b ^ 2 ) ) ) = ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) ) | 
						
							| 93 | 58 | oveq1d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( sqrt ` D ) ^ 2 ) x. ( d ^ 2 ) ) = ( D x. ( d ^ 2 ) ) ) | 
						
							| 94 | 93 | oveq2d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( c ^ 2 ) - ( ( ( sqrt ` D ) ^ 2 ) x. ( d ^ 2 ) ) ) = ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) ) | 
						
							| 95 | 92 94 | oveq12d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( a ^ 2 ) - ( ( ( sqrt ` D ) ^ 2 ) x. ( b ^ 2 ) ) ) x. ( ( c ^ 2 ) - ( ( ( sqrt ` D ) ^ 2 ) x. ( d ^ 2 ) ) ) ) = ( ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) x. ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) ) ) | 
						
							| 96 |  | simprr |  |-  ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) -> ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) | 
						
							| 97 | 96 | ad2antrr |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) | 
						
							| 98 |  | simprr |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) | 
						
							| 99 | 97 98 | oveq12d |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) x. ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) ) = ( 1 x. 1 ) ) | 
						
							| 100 |  | 1t1e1 |  |-  ( 1 x. 1 ) = 1 | 
						
							| 101 | 100 | a1i |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( 1 x. 1 ) = 1 ) | 
						
							| 102 | 95 99 101 | 3eqtrd |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( a ^ 2 ) - ( ( ( sqrt ` D ) ^ 2 ) x. ( b ^ 2 ) ) ) x. ( ( c ^ 2 ) - ( ( ( sqrt ` D ) ^ 2 ) x. ( d ^ 2 ) ) ) ) = 1 ) | 
						
							| 103 | 74 90 102 | 3eqtrd |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) - ( D x. ( ( ( a x. d ) + ( c x. b ) ) ^ 2 ) ) ) = 1 ) | 
						
							| 104 |  | oveq1 |  |-  ( e = ( ( a x. c ) + ( D x. ( d x. b ) ) ) -> ( e + ( ( sqrt ` D ) x. f ) ) = ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) + ( ( sqrt ` D ) x. f ) ) ) | 
						
							| 105 | 104 | eqeq2d |  |-  ( e = ( ( a x. c ) + ( D x. ( d x. b ) ) ) -> ( ( A x. B ) = ( e + ( ( sqrt ` D ) x. f ) ) <-> ( A x. B ) = ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) + ( ( sqrt ` D ) x. f ) ) ) ) | 
						
							| 106 |  | oveq1 |  |-  ( e = ( ( a x. c ) + ( D x. ( d x. b ) ) ) -> ( e ^ 2 ) = ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) ) | 
						
							| 107 | 106 | oveq1d |  |-  ( e = ( ( a x. c ) + ( D x. ( d x. b ) ) ) -> ( ( e ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) - ( D x. ( f ^ 2 ) ) ) ) | 
						
							| 108 | 107 | eqeq1d |  |-  ( e = ( ( a x. c ) + ( D x. ( d x. b ) ) ) -> ( ( ( e ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = 1 <-> ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = 1 ) ) | 
						
							| 109 | 105 108 | anbi12d |  |-  ( e = ( ( a x. c ) + ( D x. ( d x. b ) ) ) -> ( ( ( A x. B ) = ( e + ( ( sqrt ` D ) x. f ) ) /\ ( ( e ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = 1 ) <-> ( ( A x. B ) = ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) + ( ( sqrt ` D ) x. f ) ) /\ ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = 1 ) ) ) | 
						
							| 110 |  | oveq2 |  |-  ( f = ( ( a x. d ) + ( c x. b ) ) -> ( ( sqrt ` D ) x. f ) = ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) | 
						
							| 111 | 110 | oveq2d |  |-  ( f = ( ( a x. d ) + ( c x. b ) ) -> ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) + ( ( sqrt ` D ) x. f ) ) = ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) + ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) ) | 
						
							| 112 | 111 | eqeq2d |  |-  ( f = ( ( a x. d ) + ( c x. b ) ) -> ( ( A x. B ) = ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) + ( ( sqrt ` D ) x. f ) ) <-> ( A x. B ) = ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) + ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) ) ) | 
						
							| 113 |  | oveq1 |  |-  ( f = ( ( a x. d ) + ( c x. b ) ) -> ( f ^ 2 ) = ( ( ( a x. d ) + ( c x. b ) ) ^ 2 ) ) | 
						
							| 114 | 113 | oveq2d |  |-  ( f = ( ( a x. d ) + ( c x. b ) ) -> ( D x. ( f ^ 2 ) ) = ( D x. ( ( ( a x. d ) + ( c x. b ) ) ^ 2 ) ) ) | 
						
							| 115 | 114 | oveq2d |  |-  ( f = ( ( a x. d ) + ( c x. b ) ) -> ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) - ( D x. ( ( ( a x. d ) + ( c x. b ) ) ^ 2 ) ) ) ) | 
						
							| 116 | 115 | eqeq1d |  |-  ( f = ( ( a x. d ) + ( c x. b ) ) -> ( ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = 1 <-> ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) - ( D x. ( ( ( a x. d ) + ( c x. b ) ) ^ 2 ) ) ) = 1 ) ) | 
						
							| 117 | 112 116 | anbi12d |  |-  ( f = ( ( a x. d ) + ( c x. b ) ) -> ( ( ( A x. B ) = ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) + ( ( sqrt ` D ) x. f ) ) /\ ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = 1 ) <-> ( ( A x. B ) = ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) + ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) /\ ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) - ( D x. ( ( ( a x. d ) + ( c x. b ) ) ^ 2 ) ) ) = 1 ) ) ) | 
						
							| 118 | 109 117 | rspc2ev |  |-  ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) e. ZZ /\ ( ( a x. d ) + ( c x. b ) ) e. ZZ /\ ( ( A x. B ) = ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) + ( ( sqrt ` D ) x. ( ( a x. d ) + ( c x. b ) ) ) ) /\ ( ( ( ( a x. c ) + ( D x. ( d x. b ) ) ) ^ 2 ) - ( D x. ( ( ( a x. d ) + ( c x. b ) ) ^ 2 ) ) ) = 1 ) ) -> E. e e. ZZ E. f e. ZZ ( ( A x. B ) = ( e + ( ( sqrt ` D ) x. f ) ) /\ ( ( e ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = 1 ) ) | 
						
							| 119 | 16 19 55 103 118 | syl112anc |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> E. e e. ZZ E. f e. ZZ ( ( A x. B ) = ( e + ( ( sqrt ` D ) x. f ) ) /\ ( ( e ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = 1 ) ) | 
						
							| 120 | 2 119 | jca |  |-  ( ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) /\ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( A x. B ) e. RR /\ E. e e. ZZ E. f e. ZZ ( ( A x. B ) = ( e + ( ( sqrt ` D ) x. f ) ) /\ ( ( e ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = 1 ) ) ) | 
						
							| 121 | 120 | ex |  |-  ( ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( c e. ZZ /\ d e. ZZ ) ) -> ( ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) -> ( ( A x. B ) e. RR /\ E. e e. ZZ E. f e. ZZ ( ( A x. B ) = ( e + ( ( sqrt ` D ) x. f ) ) /\ ( ( e ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = 1 ) ) ) ) | 
						
							| 122 | 121 | rexlimdvva |  |-  ( ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) /\ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) -> ( E. c e. ZZ E. d e. ZZ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) -> ( ( A x. B ) e. RR /\ E. e e. ZZ E. f e. ZZ ( ( A x. B ) = ( e + ( ( sqrt ` D ) x. f ) ) /\ ( ( e ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = 1 ) ) ) ) | 
						
							| 123 | 122 | ex |  |-  ( ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) /\ ( a e. ZZ /\ b e. ZZ ) ) -> ( ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) -> ( E. c e. ZZ E. d e. ZZ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) -> ( ( A x. B ) e. RR /\ E. e e. ZZ E. f e. ZZ ( ( A x. B ) = ( e + ( ( sqrt ` D ) x. f ) ) /\ ( ( e ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = 1 ) ) ) ) ) | 
						
							| 124 | 123 | rexlimdvva |  |-  ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) -> ( E. a e. ZZ E. b e. ZZ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) -> ( E. c e. ZZ E. d e. ZZ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) -> ( ( A x. B ) e. RR /\ E. e e. ZZ E. f e. ZZ ( ( A x. B ) = ( e + ( ( sqrt ` D ) x. f ) ) /\ ( ( e ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = 1 ) ) ) ) ) | 
						
							| 125 | 124 | impd |  |-  ( ( D e. ( NN \ []NN ) /\ ( A e. RR /\ B e. RR ) ) -> ( ( E. a e. ZZ E. b e. ZZ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) /\ E. c e. ZZ E. d e. ZZ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) -> ( ( A x. B ) e. RR /\ E. e e. ZZ E. f e. ZZ ( ( A x. B ) = ( e + ( ( sqrt ` D ) x. f ) ) /\ ( ( e ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = 1 ) ) ) ) | 
						
							| 126 | 125 | expimpd |  |-  ( D e. ( NN \ []NN ) -> ( ( ( A e. RR /\ B e. RR ) /\ ( E. a e. ZZ E. b e. ZZ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) /\ E. c e. ZZ E. d e. ZZ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) ) -> ( ( A x. B ) e. RR /\ E. e e. ZZ E. f e. ZZ ( ( A x. B ) = ( e + ( ( sqrt ` D ) x. f ) ) /\ ( ( e ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = 1 ) ) ) ) | 
						
							| 127 |  | elpell1234qr |  |-  ( D e. ( NN \ []NN ) -> ( A e. ( Pell1234QR ` D ) <-> ( A e. RR /\ E. a e. ZZ E. b e. ZZ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) ) ) | 
						
							| 128 |  | elpell1234qr |  |-  ( D e. ( NN \ []NN ) -> ( B e. ( Pell1234QR ` D ) <-> ( B e. RR /\ E. c e. ZZ E. d e. ZZ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) ) ) | 
						
							| 129 | 127 128 | anbi12d |  |-  ( D e. ( NN \ []NN ) -> ( ( A e. ( Pell1234QR ` D ) /\ B e. ( Pell1234QR ` D ) ) <-> ( ( A e. RR /\ E. a e. ZZ E. b e. ZZ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( B e. RR /\ E. c e. ZZ E. d e. ZZ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) ) ) ) | 
						
							| 130 |  | an4 |  |-  ( ( ( A e. RR /\ E. a e. ZZ E. b e. ZZ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) ) /\ ( B e. RR /\ E. c e. ZZ E. d e. ZZ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) ) <-> ( ( A e. RR /\ B e. RR ) /\ ( E. a e. ZZ E. b e. ZZ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) /\ E. c e. ZZ E. d e. ZZ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) ) ) | 
						
							| 131 | 129 130 | bitrdi |  |-  ( D e. ( NN \ []NN ) -> ( ( A e. ( Pell1234QR ` D ) /\ B e. ( Pell1234QR ` D ) ) <-> ( ( A e. RR /\ B e. RR ) /\ ( E. a e. ZZ E. b e. ZZ ( A = ( a + ( ( sqrt ` D ) x. b ) ) /\ ( ( a ^ 2 ) - ( D x. ( b ^ 2 ) ) ) = 1 ) /\ E. c e. ZZ E. d e. ZZ ( B = ( c + ( ( sqrt ` D ) x. d ) ) /\ ( ( c ^ 2 ) - ( D x. ( d ^ 2 ) ) ) = 1 ) ) ) ) ) | 
						
							| 132 |  | elpell1234qr |  |-  ( D e. ( NN \ []NN ) -> ( ( A x. B ) e. ( Pell1234QR ` D ) <-> ( ( A x. B ) e. RR /\ E. e e. ZZ E. f e. ZZ ( ( A x. B ) = ( e + ( ( sqrt ` D ) x. f ) ) /\ ( ( e ^ 2 ) - ( D x. ( f ^ 2 ) ) ) = 1 ) ) ) ) | 
						
							| 133 | 126 131 132 | 3imtr4d |  |-  ( D e. ( NN \ []NN ) -> ( ( A e. ( Pell1234QR ` D ) /\ B e. ( Pell1234QR ` D ) ) -> ( A x. B ) e. ( Pell1234QR ` D ) ) ) | 
						
							| 134 | 133 | 3impib |  |-  ( ( D e. ( NN \ []NN ) /\ A e. ( Pell1234QR ` D ) /\ B e. ( Pell1234QR ` D ) ) -> ( A x. B ) e. ( Pell1234QR ` D ) ) |