Theorem daraptiALT 2718

Description: Alternate proof of darapti 2717, shorter but using more axioms. See comment of dariiALT 2699. (Contributed by David A. Wheeler, 27-Aug-2016.) (Proof modification is discouraged.) (New usage is discouraged.)

Hypotheses

Ref	Expression
darapti.maj	⊢ ∀𝑥(𝜑 → 𝜓)
darapti.min	⊢ ∀𝑥(𝜑 → 𝜒)
darapti.e	⊢ ∃𝑥𝜑

Assertion

Ref	Expression
daraptiALT	⊢ ∃𝑥(𝜒 ∧ 𝜓)

Proof of Theorem daraptiALT

Step	Hyp	Ref	Expression
1		darapti.e	. 2 ⊢ ∃𝑥𝜑
2		darapti.min	. . . 4 ⊢ ∀𝑥(𝜑 → 𝜒)
3	2	spi 2113	. . 3 ⊢ (𝜑 → 𝜒)
4		darapti.maj	. . . 4 ⊢ ∀𝑥(𝜑 → 𝜓)
5	4	spi 2113	. . 3 ⊢ (𝜑 → 𝜓)
6	3, 5	jca 504	. 2 ⊢ (𝜑 → (𝜒 ∧ 𝜓))
7	1, 6	eximii 1800	1 ⊢ ∃𝑥(𝜒 ∧ 𝜓)

Syntax hints:   → wi 4   ∧ wa 387  ∀wal 1506  ∃wex 1743

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1759  ax-4 1773  ax-5 1870  ax-6 1929  ax-7 1966  ax-12 2107

This theorem depends on definitions:  df-bi 199  df-an 388  df-ex 1744

This theorem is referenced by: (None)