Theorem iuneq2i 3934

Description: Equality inference for indexed union. (Contributed by NM, 22-Oct-2003.)

Hypothesis

Ref	Expression
iuneq2i.1	|- ( x e. A -> B = C )

Assertion

Ref	Expression
iuneq2i	|- U_ x e. A B = U_ x e. A C

Proof of Theorem iuneq2i

Step	Hyp	Ref	Expression
1		iuneq2 3932	. 2 |- ( A. x e. A B = C -> U_ x e. A B = U_ x e. A C )
2		iuneq2i.1	. 2 |- ( x e. A -> B = C )
3	1, 2	mprg 2554	1 |- U_ x e. A B = U_ x e. A C

Syntax hints:   -> wi 4   = wceq 1364   e. wcel 2167   U_ciun 3916

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-io 710  ax-5 1461  ax-7 1462  ax-gen 1463  ax-ie1 1507  ax-ie2 1508  ax-8 1518  ax-10 1519  ax-11 1520  ax-i12 1521  ax-bndl 1523  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-rex 2481  df-v 2765  df-in 3163  df-ss 3170  df-iun 3918

This theorem is referenced by:  dfiunv2  3952  iunrab  3964  iunid  3972  iunin1  3981  2iunin  3983  resiun1  4965  resiun2  4966  dfimafn2  5610  dfmpt  5739  rdgival  6440  uniqs  6652  imasplusg  12951  txbasval  14503