Theorem mpoeq12 5986

Description: An equality theorem for the maps-to notation. (Contributed by Mario Carneiro, 16-Dec-2013.)

Assertion

Ref	Expression
mpoeq12	|- ( ( A = C /\ B = D ) -> ( x e. A , y e. B |-> E ) = ( x e. C , y e. D |-> E ) )

Distinct variable groups:   x, y, A   x, B, y   x, C, y   x, D, y

Allowed substitution hints:   E( x, y)

Proof of Theorem mpoeq12

Step	Hyp	Ref	Expression
1		eqid 2196	. . . . 5 |- E = E
2	1	rgenw 2552	. . . 4 |- A. y e. B E = E
3	2	jctr 315	. . 3 |- ( B = D -> ( B = D /\ A. y e. B E = E ) )
4	3	ralrimivw 2571	. 2 |- ( B = D -> A. x e. A ( B = D /\ A. y e. B E = E ) )
5		mpoeq123 5985	. 2 |- ( ( A = C /\ A. x e. A ( B = D /\ A. y e. B E = E ) ) -> ( x e. A , y e. B |-> E ) = ( x e. C , y e. D |-> E ) )
6	4, 5	sylan2 286	1 |- ( ( A = C /\ B = D ) -> ( x e. A , y e. B |-> E ) = ( x e. C , y e. D |-> E ) )

Syntax hints:   -> wi 4   /\ wa 104   = wceq 1364   A.wral 2475   e. cmpo 5927

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-5 1461  ax-7 1462  ax-gen 1463  ax-ie1 1507  ax-ie2 1508  ax-8 1518  ax-11 1520  ax-4 1524  ax-17 1540  ax-i9 1544  ax-ial 1548  ax-i5r 1549  ax-ext 2178

This theorem depends on definitions:  df-bi 117  df-tru 1367  df-nf 1475  df-sb 1777  df-clab 2183  df-cleq 2189  df-clel 2192  df-nfc 2328  df-ral 2480  df-oprab 5929  df-mpo 5930

This theorem is referenced by:  seqeq1  10559  xpsval  13054  grpsubpropd2  13307  txvalex  14574  txval  14575