This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.

Metamath Proof Explorer

Theorem a1i13

Description: Add two antecedents to a wff. (Contributed by Jeff Hankins, 4-Aug-2009)

		Ref	Expression
	Hypothesis	a1i13.1	$⊢ ψ \to θ$
	Assertion	a1i13	$⊢ φ \to (ψ \to (χ \to θ))$

Step	Hyp	Ref	Expression
1		a1i13.1	$⊢ ψ \to θ$
2	1	a1d	$⊢ ψ \to (χ \to θ)$
3	2	a1i	$⊢ φ \to (ψ \to (χ \to θ))$