| Step | Hyp | Ref | Expression | 
						
							| 1 |  | icoshftf1o.1 |  |-  F = ( x e. ( A [,) B ) |-> ( x + C ) ) | 
						
							| 2 |  | icoshft |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> ( x e. ( A [,) B ) -> ( x + C ) e. ( ( A + C ) [,) ( B + C ) ) ) ) | 
						
							| 3 | 2 | ralrimiv |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> A. x e. ( A [,) B ) ( x + C ) e. ( ( A + C ) [,) ( B + C ) ) ) | 
						
							| 4 |  | readdcl |  |-  ( ( A e. RR /\ C e. RR ) -> ( A + C ) e. RR ) | 
						
							| 5 | 4 | 3adant2 |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> ( A + C ) e. RR ) | 
						
							| 6 |  | readdcl |  |-  ( ( B e. RR /\ C e. RR ) -> ( B + C ) e. RR ) | 
						
							| 7 | 6 | 3adant1 |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> ( B + C ) e. RR ) | 
						
							| 8 |  | renegcl |  |-  ( C e. RR -> -u C e. RR ) | 
						
							| 9 | 8 | 3ad2ant3 |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> -u C e. RR ) | 
						
							| 10 |  | icoshft |  |-  ( ( ( A + C ) e. RR /\ ( B + C ) e. RR /\ -u C e. RR ) -> ( y e. ( ( A + C ) [,) ( B + C ) ) -> ( y + -u C ) e. ( ( ( A + C ) + -u C ) [,) ( ( B + C ) + -u C ) ) ) ) | 
						
							| 11 | 5 7 9 10 | syl3anc |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> ( y e. ( ( A + C ) [,) ( B + C ) ) -> ( y + -u C ) e. ( ( ( A + C ) + -u C ) [,) ( ( B + C ) + -u C ) ) ) ) | 
						
							| 12 | 11 | imp |  |-  ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) -> ( y + -u C ) e. ( ( ( A + C ) + -u C ) [,) ( ( B + C ) + -u C ) ) ) | 
						
							| 13 | 7 | rexrd |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> ( B + C ) e. RR* ) | 
						
							| 14 |  | icossre |  |-  ( ( ( A + C ) e. RR /\ ( B + C ) e. RR* ) -> ( ( A + C ) [,) ( B + C ) ) C_ RR ) | 
						
							| 15 | 5 13 14 | syl2anc |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> ( ( A + C ) [,) ( B + C ) ) C_ RR ) | 
						
							| 16 | 15 | sselda |  |-  ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) -> y e. RR ) | 
						
							| 17 | 16 | recnd |  |-  ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) -> y e. CC ) | 
						
							| 18 |  | simpl3 |  |-  ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) -> C e. RR ) | 
						
							| 19 | 18 | recnd |  |-  ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) -> C e. CC ) | 
						
							| 20 | 17 19 | negsubd |  |-  ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) -> ( y + -u C ) = ( y - C ) ) | 
						
							| 21 | 5 | recnd |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> ( A + C ) e. CC ) | 
						
							| 22 |  | simp3 |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> C e. RR ) | 
						
							| 23 | 22 | recnd |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> C e. CC ) | 
						
							| 24 | 21 23 | negsubd |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> ( ( A + C ) + -u C ) = ( ( A + C ) - C ) ) | 
						
							| 25 |  | simp1 |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> A e. RR ) | 
						
							| 26 | 25 | recnd |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> A e. CC ) | 
						
							| 27 | 26 23 | pncand |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> ( ( A + C ) - C ) = A ) | 
						
							| 28 | 24 27 | eqtrd |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> ( ( A + C ) + -u C ) = A ) | 
						
							| 29 | 7 | recnd |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> ( B + C ) e. CC ) | 
						
							| 30 | 29 23 | negsubd |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> ( ( B + C ) + -u C ) = ( ( B + C ) - C ) ) | 
						
							| 31 |  | simp2 |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> B e. RR ) | 
						
							| 32 | 31 | recnd |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> B e. CC ) | 
						
							| 33 | 32 23 | pncand |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> ( ( B + C ) - C ) = B ) | 
						
							| 34 | 30 33 | eqtrd |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> ( ( B + C ) + -u C ) = B ) | 
						
							| 35 | 28 34 | oveq12d |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> ( ( ( A + C ) + -u C ) [,) ( ( B + C ) + -u C ) ) = ( A [,) B ) ) | 
						
							| 36 | 35 | adantr |  |-  ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) -> ( ( ( A + C ) + -u C ) [,) ( ( B + C ) + -u C ) ) = ( A [,) B ) ) | 
						
							| 37 | 12 20 36 | 3eltr3d |  |-  ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) -> ( y - C ) e. ( A [,) B ) ) | 
						
							| 38 |  | reueq |  |-  ( ( y - C ) e. ( A [,) B ) <-> E! x e. ( A [,) B ) x = ( y - C ) ) | 
						
							| 39 | 37 38 | sylib |  |-  ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) -> E! x e. ( A [,) B ) x = ( y - C ) ) | 
						
							| 40 | 16 | adantr |  |-  ( ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) /\ x e. ( A [,) B ) ) -> y e. RR ) | 
						
							| 41 | 40 | recnd |  |-  ( ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) /\ x e. ( A [,) B ) ) -> y e. CC ) | 
						
							| 42 |  | simpll3 |  |-  ( ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) /\ x e. ( A [,) B ) ) -> C e. RR ) | 
						
							| 43 | 42 | recnd |  |-  ( ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) /\ x e. ( A [,) B ) ) -> C e. CC ) | 
						
							| 44 |  | simpl1 |  |-  ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) -> A e. RR ) | 
						
							| 45 |  | simpl2 |  |-  ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) -> B e. RR ) | 
						
							| 46 | 45 | rexrd |  |-  ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) -> B e. RR* ) | 
						
							| 47 |  | icossre |  |-  ( ( A e. RR /\ B e. RR* ) -> ( A [,) B ) C_ RR ) | 
						
							| 48 | 44 46 47 | syl2anc |  |-  ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) -> ( A [,) B ) C_ RR ) | 
						
							| 49 | 48 | sselda |  |-  ( ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) /\ x e. ( A [,) B ) ) -> x e. RR ) | 
						
							| 50 | 49 | recnd |  |-  ( ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) /\ x e. ( A [,) B ) ) -> x e. CC ) | 
						
							| 51 | 41 43 50 | subadd2d |  |-  ( ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) /\ x e. ( A [,) B ) ) -> ( ( y - C ) = x <-> ( x + C ) = y ) ) | 
						
							| 52 |  | eqcom |  |-  ( x = ( y - C ) <-> ( y - C ) = x ) | 
						
							| 53 |  | eqcom |  |-  ( y = ( x + C ) <-> ( x + C ) = y ) | 
						
							| 54 | 51 52 53 | 3bitr4g |  |-  ( ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) /\ x e. ( A [,) B ) ) -> ( x = ( y - C ) <-> y = ( x + C ) ) ) | 
						
							| 55 | 54 | reubidva |  |-  ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) -> ( E! x e. ( A [,) B ) x = ( y - C ) <-> E! x e. ( A [,) B ) y = ( x + C ) ) ) | 
						
							| 56 | 39 55 | mpbid |  |-  ( ( ( A e. RR /\ B e. RR /\ C e. RR ) /\ y e. ( ( A + C ) [,) ( B + C ) ) ) -> E! x e. ( A [,) B ) y = ( x + C ) ) | 
						
							| 57 | 56 | ralrimiva |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> A. y e. ( ( A + C ) [,) ( B + C ) ) E! x e. ( A [,) B ) y = ( x + C ) ) | 
						
							| 58 | 1 | f1ompt |  |-  ( F : ( A [,) B ) -1-1-onto-> ( ( A + C ) [,) ( B + C ) ) <-> ( A. x e. ( A [,) B ) ( x + C ) e. ( ( A + C ) [,) ( B + C ) ) /\ A. y e. ( ( A + C ) [,) ( B + C ) ) E! x e. ( A [,) B ) y = ( x + C ) ) ) | 
						
							| 59 | 3 57 58 | sylanbrc |  |-  ( ( A e. RR /\ B e. RR /\ C e. RR ) -> F : ( A [,) B ) -1-1-onto-> ( ( A + C ) [,) ( B + C ) ) ) |