Theorem unieqi 3799

Description: Inference of equality of two class unions. (Contributed by NM, 30-Aug-1993.)

Hypothesis

Ref	Expression
unieqi.1	|- A = B

Assertion

Ref	Expression
unieqi	|- U. A = U. B

Proof of Theorem unieqi

Step	Hyp	Ref	Expression
1		unieqi.1	. 2 |- A = B
2		unieq 3798	. 2 |- ( A = B -> U. A = U. B )
3	1, 2	ax-mp 5	1 |- U. A = U. B

Syntax hints:   = wceq 1343   U.cuni 3789

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 699  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-10 1493  ax-11 1494  ax-i12 1495  ax-bndl 1497  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523  ax-ext 2147

This theorem depends on definitions:  df-bi 116  df-tru 1346  df-nf 1449  df-sb 1751  df-clab 2152  df-cleq 2158  df-clel 2161  df-nfc 2297  df-rex 2450  df-uni 3790

This theorem is referenced by:  elunirab  3802  unisn  3805  uniop  4233  unisuc  4391  unisucg  4392  univ  4454  dfiun3g  4861  op1sta  5085  op2nda  5088  dfdm2  5138  iotajust  5152  dfiota2  5154  cbviota  5158  sb8iota  5160  dffv4g  5483  funfvdm2f  5551  riotauni  5804  1st0  6112  2nd0  6113  unielxp  6142  brtpos0  6220  recsfval  6283  uniqs  6559  xpassen  6796  sup00  6968  suplocexprlemell  7654  uptx  12914