Theorem el3v13

Description: New way ( elv , and the theorems beginning with "el2v" or "el3v") to shorten some proofs. (Contributed by Peter Mazsa, 11-Jul-2021)

	Ref	Expression
Hypothesis	el3v13.1	$$⊢\left(x\in \mathrm{V}\wedge \psi \wedge z\in \mathrm{V}\right)\to \theta$$
Assertion	el3v13	$$⊢\psi \to \theta$$

Proof

Step	Hyp	Ref	Expression
1		el3v13.1	$$⊢\left(x\in \mathrm{V}\wedge \psi \wedge z\in \mathrm{V}\right)\to \theta$$
2	1	el3v3	$$⊢\left(x\in \mathrm{V}\wedge \psi \right)\to \theta$$
3	2	el2v1	$$⊢\psi \to \theta$$