| Step | Hyp | Ref | Expression | 
						
							| 1 |  | xpmapen.1 | ⊢ 𝐴  ∈  V | 
						
							| 2 |  | xpmapen.2 | ⊢ 𝐵  ∈  V | 
						
							| 3 |  | xpmapen.3 | ⊢ 𝐶  ∈  V | 
						
							| 4 |  | xpmapenlem.4 | ⊢ 𝐷  =  ( 𝑧  ∈  𝐶  ↦  ( 1st  ‘ ( 𝑥 ‘ 𝑧 ) ) ) | 
						
							| 5 |  | xpmapenlem.5 | ⊢ 𝑅  =  ( 𝑧  ∈  𝐶  ↦  ( 2nd  ‘ ( 𝑥 ‘ 𝑧 ) ) ) | 
						
							| 6 |  | xpmapenlem.6 | ⊢ 𝑆  =  ( 𝑧  ∈  𝐶  ↦  〈 ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ,  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) 〉 ) | 
						
							| 7 |  | ovex | ⊢ ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∈  V | 
						
							| 8 |  | ovex | ⊢ ( 𝐴  ↑m  𝐶 )  ∈  V | 
						
							| 9 |  | ovex | ⊢ ( 𝐵  ↑m  𝐶 )  ∈  V | 
						
							| 10 | 8 9 | xpex | ⊢ ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) )  ∈  V | 
						
							| 11 | 1 2 | xpex | ⊢ ( 𝐴  ×  𝐵 )  ∈  V | 
						
							| 12 | 11 3 | elmap | ⊢ ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ↔  𝑥 : 𝐶 ⟶ ( 𝐴  ×  𝐵 ) ) | 
						
							| 13 |  | ffvelcdm | ⊢ ( ( 𝑥 : 𝐶 ⟶ ( 𝐴  ×  𝐵 )  ∧  𝑧  ∈  𝐶 )  →  ( 𝑥 ‘ 𝑧 )  ∈  ( 𝐴  ×  𝐵 ) ) | 
						
							| 14 | 12 13 | sylanb | ⊢ ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑧  ∈  𝐶 )  →  ( 𝑥 ‘ 𝑧 )  ∈  ( 𝐴  ×  𝐵 ) ) | 
						
							| 15 |  | xp1st | ⊢ ( ( 𝑥 ‘ 𝑧 )  ∈  ( 𝐴  ×  𝐵 )  →  ( 1st  ‘ ( 𝑥 ‘ 𝑧 ) )  ∈  𝐴 ) | 
						
							| 16 | 14 15 | syl | ⊢ ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑧  ∈  𝐶 )  →  ( 1st  ‘ ( 𝑥 ‘ 𝑧 ) )  ∈  𝐴 ) | 
						
							| 17 | 16 4 | fmptd | ⊢ ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  →  𝐷 : 𝐶 ⟶ 𝐴 ) | 
						
							| 18 | 1 3 | elmap | ⊢ ( 𝐷  ∈  ( 𝐴  ↑m  𝐶 )  ↔  𝐷 : 𝐶 ⟶ 𝐴 ) | 
						
							| 19 | 17 18 | sylibr | ⊢ ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  →  𝐷  ∈  ( 𝐴  ↑m  𝐶 ) ) | 
						
							| 20 |  | xp2nd | ⊢ ( ( 𝑥 ‘ 𝑧 )  ∈  ( 𝐴  ×  𝐵 )  →  ( 2nd  ‘ ( 𝑥 ‘ 𝑧 ) )  ∈  𝐵 ) | 
						
							| 21 | 14 20 | syl | ⊢ ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑧  ∈  𝐶 )  →  ( 2nd  ‘ ( 𝑥 ‘ 𝑧 ) )  ∈  𝐵 ) | 
						
							| 22 | 21 5 | fmptd | ⊢ ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  →  𝑅 : 𝐶 ⟶ 𝐵 ) | 
						
							| 23 | 2 3 | elmap | ⊢ ( 𝑅  ∈  ( 𝐵  ↑m  𝐶 )  ↔  𝑅 : 𝐶 ⟶ 𝐵 ) | 
						
							| 24 | 22 23 | sylibr | ⊢ ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  →  𝑅  ∈  ( 𝐵  ↑m  𝐶 ) ) | 
						
							| 25 | 19 24 | opelxpd | ⊢ ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  →  〈 𝐷 ,  𝑅 〉  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) ) | 
						
							| 26 |  | xp1st | ⊢ ( 𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) )  →  ( 1st  ‘ 𝑦 )  ∈  ( 𝐴  ↑m  𝐶 ) ) | 
						
							| 27 | 1 3 | elmap | ⊢ ( ( 1st  ‘ 𝑦 )  ∈  ( 𝐴  ↑m  𝐶 )  ↔  ( 1st  ‘ 𝑦 ) : 𝐶 ⟶ 𝐴 ) | 
						
							| 28 | 26 27 | sylib | ⊢ ( 𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) )  →  ( 1st  ‘ 𝑦 ) : 𝐶 ⟶ 𝐴 ) | 
						
							| 29 | 28 | ffvelcdmda | ⊢ ( ( 𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) )  ∧  𝑧  ∈  𝐶 )  →  ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 )  ∈  𝐴 ) | 
						
							| 30 |  | xp2nd | ⊢ ( 𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) )  →  ( 2nd  ‘ 𝑦 )  ∈  ( 𝐵  ↑m  𝐶 ) ) | 
						
							| 31 | 2 3 | elmap | ⊢ ( ( 2nd  ‘ 𝑦 )  ∈  ( 𝐵  ↑m  𝐶 )  ↔  ( 2nd  ‘ 𝑦 ) : 𝐶 ⟶ 𝐵 ) | 
						
							| 32 | 30 31 | sylib | ⊢ ( 𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) )  →  ( 2nd  ‘ 𝑦 ) : 𝐶 ⟶ 𝐵 ) | 
						
							| 33 | 32 | ffvelcdmda | ⊢ ( ( 𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) )  ∧  𝑧  ∈  𝐶 )  →  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 )  ∈  𝐵 ) | 
						
							| 34 | 29 33 | opelxpd | ⊢ ( ( 𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) )  ∧  𝑧  ∈  𝐶 )  →  〈 ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ,  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) 〉  ∈  ( 𝐴  ×  𝐵 ) ) | 
						
							| 35 | 34 6 | fmptd | ⊢ ( 𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) )  →  𝑆 : 𝐶 ⟶ ( 𝐴  ×  𝐵 ) ) | 
						
							| 36 | 11 3 | elmap | ⊢ ( 𝑆  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ↔  𝑆 : 𝐶 ⟶ ( 𝐴  ×  𝐵 ) ) | 
						
							| 37 | 35 36 | sylibr | ⊢ ( 𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) )  →  𝑆  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 ) ) | 
						
							| 38 |  | 1st2nd2 | ⊢ ( 𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) )  →  𝑦  =  〈 ( 1st  ‘ 𝑦 ) ,  ( 2nd  ‘ 𝑦 ) 〉 ) | 
						
							| 39 | 38 | ad2antlr | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  →  𝑦  =  〈 ( 1st  ‘ 𝑦 ) ,  ( 2nd  ‘ 𝑦 ) 〉 ) | 
						
							| 40 | 28 | feqmptd | ⊢ ( 𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) )  →  ( 1st  ‘ 𝑦 )  =  ( 𝑧  ∈  𝐶  ↦  ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ) ) | 
						
							| 41 | 40 | ad2antlr | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  →  ( 1st  ‘ 𝑦 )  =  ( 𝑧  ∈  𝐶  ↦  ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ) ) | 
						
							| 42 |  | simplr | ⊢ ( ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  ∧  𝑧  ∈  𝐶 )  →  𝑥  =  𝑆 ) | 
						
							| 43 | 42 | fveq1d | ⊢ ( ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  ∧  𝑧  ∈  𝐶 )  →  ( 𝑥 ‘ 𝑧 )  =  ( 𝑆 ‘ 𝑧 ) ) | 
						
							| 44 |  | opex | ⊢ 〈 ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ,  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) 〉  ∈  V | 
						
							| 45 | 6 | fvmpt2 | ⊢ ( ( 𝑧  ∈  𝐶  ∧  〈 ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ,  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) 〉  ∈  V )  →  ( 𝑆 ‘ 𝑧 )  =  〈 ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ,  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) 〉 ) | 
						
							| 46 | 44 45 | mpan2 | ⊢ ( 𝑧  ∈  𝐶  →  ( 𝑆 ‘ 𝑧 )  =  〈 ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ,  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) 〉 ) | 
						
							| 47 | 46 | adantl | ⊢ ( ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  ∧  𝑧  ∈  𝐶 )  →  ( 𝑆 ‘ 𝑧 )  =  〈 ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ,  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) 〉 ) | 
						
							| 48 | 43 47 | eqtrd | ⊢ ( ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  ∧  𝑧  ∈  𝐶 )  →  ( 𝑥 ‘ 𝑧 )  =  〈 ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ,  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) 〉 ) | 
						
							| 49 | 48 | fveq2d | ⊢ ( ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  ∧  𝑧  ∈  𝐶 )  →  ( 1st  ‘ ( 𝑥 ‘ 𝑧 ) )  =  ( 1st  ‘ 〈 ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ,  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) 〉 ) ) | 
						
							| 50 |  | fvex | ⊢ ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 )  ∈  V | 
						
							| 51 |  | fvex | ⊢ ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 )  ∈  V | 
						
							| 52 | 50 51 | op1st | ⊢ ( 1st  ‘ 〈 ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ,  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) 〉 )  =  ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) | 
						
							| 53 | 49 52 | eqtrdi | ⊢ ( ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  ∧  𝑧  ∈  𝐶 )  →  ( 1st  ‘ ( 𝑥 ‘ 𝑧 ) )  =  ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ) | 
						
							| 54 | 53 | mpteq2dva | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  →  ( 𝑧  ∈  𝐶  ↦  ( 1st  ‘ ( 𝑥 ‘ 𝑧 ) ) )  =  ( 𝑧  ∈  𝐶  ↦  ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ) ) | 
						
							| 55 | 4 54 | eqtrid | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  →  𝐷  =  ( 𝑧  ∈  𝐶  ↦  ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ) ) | 
						
							| 56 | 41 55 | eqtr4d | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  →  ( 1st  ‘ 𝑦 )  =  𝐷 ) | 
						
							| 57 | 32 | feqmptd | ⊢ ( 𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) )  →  ( 2nd  ‘ 𝑦 )  =  ( 𝑧  ∈  𝐶  ↦  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) ) ) | 
						
							| 58 | 57 | ad2antlr | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  →  ( 2nd  ‘ 𝑦 )  =  ( 𝑧  ∈  𝐶  ↦  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) ) ) | 
						
							| 59 | 48 | fveq2d | ⊢ ( ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  ∧  𝑧  ∈  𝐶 )  →  ( 2nd  ‘ ( 𝑥 ‘ 𝑧 ) )  =  ( 2nd  ‘ 〈 ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ,  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) 〉 ) ) | 
						
							| 60 | 50 51 | op2nd | ⊢ ( 2nd  ‘ 〈 ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ,  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) 〉 )  =  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) | 
						
							| 61 | 59 60 | eqtrdi | ⊢ ( ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  ∧  𝑧  ∈  𝐶 )  →  ( 2nd  ‘ ( 𝑥 ‘ 𝑧 ) )  =  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) ) | 
						
							| 62 | 61 | mpteq2dva | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  →  ( 𝑧  ∈  𝐶  ↦  ( 2nd  ‘ ( 𝑥 ‘ 𝑧 ) ) )  =  ( 𝑧  ∈  𝐶  ↦  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) ) ) | 
						
							| 63 | 5 62 | eqtrid | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  →  𝑅  =  ( 𝑧  ∈  𝐶  ↦  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) ) ) | 
						
							| 64 | 58 63 | eqtr4d | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  →  ( 2nd  ‘ 𝑦 )  =  𝑅 ) | 
						
							| 65 | 56 64 | opeq12d | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  →  〈 ( 1st  ‘ 𝑦 ) ,  ( 2nd  ‘ 𝑦 ) 〉  =  〈 𝐷 ,  𝑅 〉 ) | 
						
							| 66 | 39 65 | eqtrd | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑥  =  𝑆 )  →  𝑦  =  〈 𝐷 ,  𝑅 〉 ) | 
						
							| 67 |  | simpll | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 ) ) | 
						
							| 68 | 67 12 | sylib | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  𝑥 : 𝐶 ⟶ ( 𝐴  ×  𝐵 ) ) | 
						
							| 69 | 68 | feqmptd | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  𝑥  =  ( 𝑧  ∈  𝐶  ↦  ( 𝑥 ‘ 𝑧 ) ) ) | 
						
							| 70 |  | simpr | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  𝑦  =  〈 𝐷 ,  𝑅 〉 ) | 
						
							| 71 | 70 | fveq2d | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  ( 1st  ‘ 𝑦 )  =  ( 1st  ‘ 〈 𝐷 ,  𝑅 〉 ) ) | 
						
							| 72 | 19 | ad2antrr | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  𝐷  ∈  ( 𝐴  ↑m  𝐶 ) ) | 
						
							| 73 | 24 | ad2antrr | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  𝑅  ∈  ( 𝐵  ↑m  𝐶 ) ) | 
						
							| 74 |  | op1stg | ⊢ ( ( 𝐷  ∈  ( 𝐴  ↑m  𝐶 )  ∧  𝑅  ∈  ( 𝐵  ↑m  𝐶 ) )  →  ( 1st  ‘ 〈 𝐷 ,  𝑅 〉 )  =  𝐷 ) | 
						
							| 75 | 72 73 74 | syl2anc | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  ( 1st  ‘ 〈 𝐷 ,  𝑅 〉 )  =  𝐷 ) | 
						
							| 76 | 71 75 | eqtrd | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  ( 1st  ‘ 𝑦 )  =  𝐷 ) | 
						
							| 77 | 76 | fveq1d | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 )  =  ( 𝐷 ‘ 𝑧 ) ) | 
						
							| 78 |  | fvex | ⊢ ( 1st  ‘ ( 𝑥 ‘ 𝑧 ) )  ∈  V | 
						
							| 79 | 4 | fvmpt2 | ⊢ ( ( 𝑧  ∈  𝐶  ∧  ( 1st  ‘ ( 𝑥 ‘ 𝑧 ) )  ∈  V )  →  ( 𝐷 ‘ 𝑧 )  =  ( 1st  ‘ ( 𝑥 ‘ 𝑧 ) ) ) | 
						
							| 80 | 78 79 | mpan2 | ⊢ ( 𝑧  ∈  𝐶  →  ( 𝐷 ‘ 𝑧 )  =  ( 1st  ‘ ( 𝑥 ‘ 𝑧 ) ) ) | 
						
							| 81 | 77 80 | sylan9eq | ⊢ ( ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  ∧  𝑧  ∈  𝐶 )  →  ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 )  =  ( 1st  ‘ ( 𝑥 ‘ 𝑧 ) ) ) | 
						
							| 82 | 70 | fveq2d | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  ( 2nd  ‘ 𝑦 )  =  ( 2nd  ‘ 〈 𝐷 ,  𝑅 〉 ) ) | 
						
							| 83 |  | op2ndg | ⊢ ( ( 𝐷  ∈  ( 𝐴  ↑m  𝐶 )  ∧  𝑅  ∈  ( 𝐵  ↑m  𝐶 ) )  →  ( 2nd  ‘ 〈 𝐷 ,  𝑅 〉 )  =  𝑅 ) | 
						
							| 84 | 72 73 83 | syl2anc | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  ( 2nd  ‘ 〈 𝐷 ,  𝑅 〉 )  =  𝑅 ) | 
						
							| 85 | 82 84 | eqtrd | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  ( 2nd  ‘ 𝑦 )  =  𝑅 ) | 
						
							| 86 | 85 | fveq1d | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 )  =  ( 𝑅 ‘ 𝑧 ) ) | 
						
							| 87 |  | fvex | ⊢ ( 2nd  ‘ ( 𝑥 ‘ 𝑧 ) )  ∈  V | 
						
							| 88 | 5 | fvmpt2 | ⊢ ( ( 𝑧  ∈  𝐶  ∧  ( 2nd  ‘ ( 𝑥 ‘ 𝑧 ) )  ∈  V )  →  ( 𝑅 ‘ 𝑧 )  =  ( 2nd  ‘ ( 𝑥 ‘ 𝑧 ) ) ) | 
						
							| 89 | 87 88 | mpan2 | ⊢ ( 𝑧  ∈  𝐶  →  ( 𝑅 ‘ 𝑧 )  =  ( 2nd  ‘ ( 𝑥 ‘ 𝑧 ) ) ) | 
						
							| 90 | 86 89 | sylan9eq | ⊢ ( ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  ∧  𝑧  ∈  𝐶 )  →  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 )  =  ( 2nd  ‘ ( 𝑥 ‘ 𝑧 ) ) ) | 
						
							| 91 | 81 90 | opeq12d | ⊢ ( ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  ∧  𝑧  ∈  𝐶 )  →  〈 ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ,  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) 〉  =  〈 ( 1st  ‘ ( 𝑥 ‘ 𝑧 ) ) ,  ( 2nd  ‘ ( 𝑥 ‘ 𝑧 ) ) 〉 ) | 
						
							| 92 | 68 | ffvelcdmda | ⊢ ( ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  ∧  𝑧  ∈  𝐶 )  →  ( 𝑥 ‘ 𝑧 )  ∈  ( 𝐴  ×  𝐵 ) ) | 
						
							| 93 |  | 1st2nd2 | ⊢ ( ( 𝑥 ‘ 𝑧 )  ∈  ( 𝐴  ×  𝐵 )  →  ( 𝑥 ‘ 𝑧 )  =  〈 ( 1st  ‘ ( 𝑥 ‘ 𝑧 ) ) ,  ( 2nd  ‘ ( 𝑥 ‘ 𝑧 ) ) 〉 ) | 
						
							| 94 | 92 93 | syl | ⊢ ( ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  ∧  𝑧  ∈  𝐶 )  →  ( 𝑥 ‘ 𝑧 )  =  〈 ( 1st  ‘ ( 𝑥 ‘ 𝑧 ) ) ,  ( 2nd  ‘ ( 𝑥 ‘ 𝑧 ) ) 〉 ) | 
						
							| 95 | 91 94 | eqtr4d | ⊢ ( ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  ∧  𝑧  ∈  𝐶 )  →  〈 ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ,  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) 〉  =  ( 𝑥 ‘ 𝑧 ) ) | 
						
							| 96 | 95 | mpteq2dva | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  ( 𝑧  ∈  𝐶  ↦  〈 ( ( 1st  ‘ 𝑦 ) ‘ 𝑧 ) ,  ( ( 2nd  ‘ 𝑦 ) ‘ 𝑧 ) 〉 )  =  ( 𝑧  ∈  𝐶  ↦  ( 𝑥 ‘ 𝑧 ) ) ) | 
						
							| 97 | 6 96 | eqtrid | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  𝑆  =  ( 𝑧  ∈  𝐶  ↦  ( 𝑥 ‘ 𝑧 ) ) ) | 
						
							| 98 | 69 97 | eqtr4d | ⊢ ( ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  ∧  𝑦  =  〈 𝐷 ,  𝑅 〉 )  →  𝑥  =  𝑆 ) | 
						
							| 99 | 66 98 | impbida | ⊢ ( ( 𝑥  ∈  ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ∧  𝑦  ∈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) )  →  ( 𝑥  =  𝑆  ↔  𝑦  =  〈 𝐷 ,  𝑅 〉 ) ) | 
						
							| 100 | 7 10 25 37 99 | en3i | ⊢ ( ( 𝐴  ×  𝐵 )  ↑m  𝐶 )  ≈  ( ( 𝐴  ↑m  𝐶 )  ×  ( 𝐵  ↑m  𝐶 ) ) |