Theorem moanimlem 2606

Description: Factor out the common proof skeleton of moanimv 2607 and moanim 2608. (Contributed by NM, 3-Dec-2001.) (Proof shortened by Wolf Lammen, 24-Dec-2018.) Factor out common proof lines. (Revised by Wolf Lammen, 8-Feb-2023.)

Hypotheses

Ref	Expression
moanimlem.1	⊢ (𝜑 → (∃*𝑥𝜓 ↔ ∃*𝑥(𝜑 ∧ 𝜓)))
moanimlem.2	⊢ (∃𝑥(𝜑 ∧ 𝜓) → 𝜑)

Assertion

Ref	Expression
moanimlem	⊢ (∃*𝑥(𝜑 ∧ 𝜓) ↔ (𝜑 → ∃*𝑥𝜓))

Proof of Theorem moanimlem

Step	Hyp	Ref	Expression
1		moanimlem.1	. . 3 ⊢ (𝜑 → (∃*𝑥𝜓 ↔ ∃*𝑥(𝜑 ∧ 𝜓)))
2	1	biimprcd 249	. 2 ⊢ (∃*𝑥(𝜑 ∧ 𝜓) → (𝜑 → ∃*𝑥𝜓))
3		moanimlem.2	. . . 4 ⊢ (∃𝑥(𝜑 ∧ 𝜓) → 𝜑)
4		nexmo 2527	. . . 4 ⊢ (¬ ∃𝑥(𝜑 ∧ 𝜓) → ∃*𝑥(𝜑 ∧ 𝜓))
5	3, 4	nsyl5 159	. . 3 ⊢ (¬ 𝜑 → ∃*𝑥(𝜑 ∧ 𝜓))
6		moan 2538	. . 3 ⊢ (∃*𝑥𝜓 → ∃*𝑥(𝜑 ∧ 𝜓))
7	5, 6	ja 186	. 2 ⊢ ((𝜑 → ∃*𝑥𝜓) → ∃*𝑥(𝜑 ∧ 𝜓))
8	2, 7	impbii 208	1 ⊢ (∃*𝑥(𝜑 ∧ 𝜓) ↔ (𝜑 → ∃*𝑥𝜓))

Syntax hints:   → wi 4   ↔ wb 205   ∧ wa 395  ∃wex 1773  ∃*wmo 2524

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1789  ax-4 1803  ax-5 1905  ax-6 1963

This theorem depends on definitions:  df-bi 206  df-an 396  df-ex 1774  df-mo 2526

This theorem is referenced by:  moanimv  2607  moanim  2608