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Metamath Proof Explorer

Theorem 4re

Description: The number 4 is real. (Contributed by NM, 27-May-1999)

		Ref	Expression
	Assertion	4re	$⊢ 4 \in ℝ$

Step	Hyp	Ref	Expression
1		df-4	$⊢ 4 = 3 + 1$
2		3re	$⊢ 3 \in ℝ$
3		1re	$⊢ 1 \in ℝ$
4	2 3	readdcli	$⊢ 3 + 1 \in ℝ$
5	1 4	eqeltri	$⊢ 4 \in ℝ$