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

Metamath Proof Explorer

Theorem 1p2e3ALT

Description: Alternate proof of 1p2e3 , shorter but using more axioms. (Contributed by David A. Wheeler, 8-Dec-2018) (New usage is discouraged.) (Proof modification is discouraged.)

		Ref	Expression
	Assertion	1p2e3ALT	$⊢ 1 + 2 = 3$

Proof

Step	Hyp	Ref	Expression
1		2cn	$⊢ 2 \in ℂ$
2		ax-1cn	$⊢ 1 \in ℂ$
3		2p1e3	$⊢ 2 + 1 = 3$
4	1 2 3	addcomli	$⊢ 1 + 2 = 3$