Theorem bnj1239 35202

Description: First-order logic and set theory. (Contributed by Jonathan Ben-Naim, 3-Jun-2011.) (New usage is discouraged.)

Assertion

Ref	Expression
bnj1239	⊢ (∃𝑥 ∈ 𝐴 (𝜓 ∧ 𝜒) → ∃𝑥 ∈ 𝐴 𝜓)

Proof of Theorem bnj1239

Step	Hyp	Ref	Expression
1		simpl 487	. 2 ⊢ ((𝜓 ∧ 𝜒) → 𝜓)
2	1	reximi 3102	1 ⊢ (∃𝑥 ∈ 𝐴 (𝜓 ∧ 𝜒) → ∃𝑥 ∈ 𝐴 𝜓)

This proof depends on syntax axioms:   → wi 4   ∧ wa 400  ∃wrex 3088

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1824  ax-4 1838

This proof depends on definitions:  df-bi 210  df-an 401  df-ex 1809  df-rex 3089

This theorem is used by:  bnj1238  35203  bnj1299  35215  bnj66  35257