Metamath Proof Explorer

Theorem bnj643

Description: /\ -manipulation. (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)

		Ref	Expression
	Assertion	bnj643	$⊢ (φ \land ψ \land χ \land θ) \to ψ$

Step	Hyp	Ref	Expression
1		bnj291	$⊢ (φ \land ψ \land χ \land θ) \leftrightarrow ((φ \land χ \land θ) \land ψ)$
2	1	simprbi	$⊢ (φ \land ψ \land χ \land θ) \to ψ$