| Step | Hyp | Ref | Expression | 
						
							| 1 |  | opprbas.1 |  | 
						
							| 2 |  | eqid |  | 
						
							| 3 | 1 2 | opprbas |  | 
						
							| 4 | 3 | a1i |  | 
						
							| 5 |  | eqid |  | 
						
							| 6 | 1 5 | oppradd |  | 
						
							| 7 | 6 | a1i |  | 
						
							| 8 |  | eqidd |  | 
						
							| 9 |  | rngabl |  | 
						
							| 10 | 3 6 | ablprop |  | 
						
							| 11 | 9 10 | sylib |  | 
						
							| 12 |  | eqid |  | 
						
							| 13 |  | eqid |  | 
						
							| 14 | 2 12 1 13 | opprmul |  | 
						
							| 15 | 2 12 | rngcl |  | 
						
							| 16 | 15 | 3com23 |  | 
						
							| 17 | 14 16 | eqeltrid |  | 
						
							| 18 |  | simpl |  | 
						
							| 19 |  | simpr3 |  | 
						
							| 20 |  | simpr2 |  | 
						
							| 21 |  | simpr1 |  | 
						
							| 22 | 2 12 | rngass |  | 
						
							| 23 | 18 19 20 21 22 | syl13anc |  | 
						
							| 24 | 23 | eqcomd |  | 
						
							| 25 | 14 | oveq1i |  | 
						
							| 26 | 2 12 1 13 | opprmul |  | 
						
							| 27 | 25 26 | eqtri |  | 
						
							| 28 | 2 12 1 13 | opprmul |  | 
						
							| 29 | 28 | oveq2i |  | 
						
							| 30 | 2 12 1 13 | opprmul |  | 
						
							| 31 | 29 30 | eqtri |  | 
						
							| 32 | 24 27 31 | 3eqtr4g |  | 
						
							| 33 | 2 5 12 | rngdir |  | 
						
							| 34 | 18 20 19 21 33 | syl13anc |  | 
						
							| 35 | 2 12 1 13 | opprmul |  | 
						
							| 36 | 2 12 1 13 | opprmul |  | 
						
							| 37 | 14 36 | oveq12i |  | 
						
							| 38 | 34 35 37 | 3eqtr4g |  | 
						
							| 39 | 2 5 12 | rngdi |  | 
						
							| 40 | 18 19 21 20 39 | syl13anc |  | 
						
							| 41 | 2 12 1 13 | opprmul |  | 
						
							| 42 | 36 28 | oveq12i |  | 
						
							| 43 | 40 41 42 | 3eqtr4g |  | 
						
							| 44 | 4 7 8 11 17 32 38 43 | isrngd |  |