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Metamath Proof Explorer

Theorem epr

Description: Euler's constant _e is a positive real. (Contributed by Jeff Hankins, 22-Nov-2008)

		Ref	Expression
	Assertion	epr	$⊢ e \in ℝ^{+}$

Step	Hyp	Ref	Expression
1		ere	$⊢ e \in ℝ$
2		epos	$⊢ 0 < e$
3	1 2	elrpii	$⊢ e \in ℝ^{+}$