Theorem cbvdisjv 4115

Description: Change bound variables in a disjoint collection. (Contributed by Mario Carneiro, 11-Dec-2016.)

Hypothesis

Ref	Expression
cbvdisjv.1	|- ( x = y -> B = C )

Assertion

Ref	Expression
cbvdisjv	|- (Disj x e. A B <-> Disj y e. A C )

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

Allowed substitution hints:   B( x)   C( y)

Proof of Theorem cbvdisjv

Step	Hyp	Ref	Expression
1		nfcv 2392	. 2 |- F/_ y B
2		nfcv 2392	. 2 |- F/_ x C
3		cbvdisjv.1	. 2 |- ( x = y -> B = C )
4	1, 2, 3	cbvdisj 4114	1 |- (Disj x e. A B <-> Disj y e. A C )

Syntax hints:   -> wi 4   <-> wb 105   = wceq 1402  Disj wdisj 4104

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 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-ext 2220

This theorem depends on definitions:  df-bi 117  df-tru 1405  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-cleq 2231  df-clel 2234  df-nfc 2381  df-rex 2534  df-reu 2535  df-rmo 2536  df-disj 4105

This theorem is referenced by: (None)