Theorem exbid 2231

Description: Formula-building rule for existential quantifier (deduction form). (Contributed by Mario Carneiro, 24-Sep-2016.)

Hypotheses

Ref	Expression
albid.1	⊢ Ⅎ𝑥𝜑
albid.2	⊢ (𝜑 → (𝜓 ↔ 𝜒))

Assertion

Ref	Expression
exbid	⊢ (𝜑 → (∃𝑥𝜓 ↔ ∃𝑥𝜒))

Proof of Theorem exbid

Step	Hyp	Ref	Expression
1		albid.1	. . 3 ⊢ Ⅎ𝑥𝜑
2	1	nf5ri 2203	. 2 ⊢ (𝜑 → ∀𝑥𝜑)
3		albid.2	. 2 ⊢ (𝜑 → (𝜓 ↔ 𝜒))
4	2, 3	exbidh 1869	1 ⊢ (𝜑 → (∃𝑥𝜓 ↔ ∃𝑥𝜒))

Syntax hints:   → wi 4   ↔ wb 206  ∃wex 1781  Ⅎwnf 1785

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1912  ax-6 1969  ax-7 2010  ax-12 2185

This theorem depends on definitions:  df-bi 207  df-ex 1782  df-nf 1786

This theorem is referenced by:  nfbidf  2232  drex2  2447  rexbida  3250  opabbid  5151  zfrepclf  5227  dfid3  5524  oprabbid  7427  axrepndlem1  10510  axrepndlem2  10511  axrepnd  10512  axpowndlem2  10516  axpowndlem3  10517  axpowndlem4  10518  axregnd  10522  axinfndlem1  10523  axinfnd  10524  axacndlem4  10528  axacndlem5  10529  axacnd  10530  opabdm  32703  opabrn  32704  axtcond  36680  pm14.122b  44872  pm14.123b  44875  modelaxreplem3  45429