Theorem ancomst

Description: Closed form of ancoms . (Contributed by Alan Sare, 31-Dec-2011)

	Ref	Expression
Assertion	ancomst	$$⊢\left(\left(\phi \wedge \psi \right)\to \chi \right)\leftrightarrow \left(\left(\psi \wedge \phi \right)\to \chi \right)$$

Proof

Step	Hyp	Ref	Expression
1		ancom	$$⊢\left(\phi \wedge \psi \right)\leftrightarrow \left(\psi \wedge \phi \right)$$
2	1	imbi1i	$$⊢\left(\left(\phi \wedge \psi \right)\to \chi \right)\leftrightarrow \left(\left(\psi \wedge \phi \right)\to \chi \right)$$