Theorem cbvdisjv 5123

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 ∈ 𝐴 𝐵 ↔ Disj 𝑦 ∈ 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 2901	. 2 ⊢ Ⅎ𝑦𝐵
2		nfcv 2901	. 2 ⊢ Ⅎ𝑥𝐶
3		cbvdisjv.1	. 2 ⊢ (𝑥 = 𝑦 → 𝐵 = 𝐶)
4	1, 2, 3	cbvdisj 5122	1 ⊢ (Disj 𝑥 ∈ 𝐴 𝐵 ↔ Disj 𝑦 ∈ 𝐴 𝐶)

Syntax hints:   → wi 4   ↔ wb 205   = wceq 1539  Disj wdisj 5112

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1911  ax-6 1969  ax-7 2009  ax-8 2106  ax-9 2114  ax-11 2152  ax-12 2169  ax-ext 2701

This theorem depends on definitions:  df-bi 206  df-an 395  df-or 844  df-tru 1542  df-ex 1780  df-nf 1784  df-mo 2532  df-cleq 2722  df-clel 2808  df-nfc 2883  df-rmo 3374  df-disj 5113

This theorem is referenced by:  uniioombllem4  25335  hashunif  32285  tocyccntz  32573  totprob  33724  disjrnmpt2  44185  ismeannd  45481  psmeasure  45485  volmea  45488  meaiuninclem  45494  caratheodorylem1  45540  caratheodory  45542