Theorem bnj1239

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

	Ref	Expression
Assertion	bnj1239	$$⊢\exists x\in A\left(\psi \wedge \chi \right)\to \exists x\in A\psi$$

Proof

Step	Hyp	Ref	Expression
1		simpl	$$⊢\left(\psi \wedge \chi \right)\to \psi$$
2	1	reximi	$$⊢\exists x\in A\left(\psi \wedge \chi \right)\to \exists x\in A\psi$$