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Metamath Proof Explorer

Theorem letop

Description: The topology of the extended reals. (Contributed by Mario Carneiro, 3-Sep-2015)

		Ref	Expression
	Assertion	letop	$⊢ ordTop (\leq) \in Top$

Step	Hyp	Ref	Expression
1		letopon	$⊢ ordTop (\leq) \in TopOn (ℝ^{*})$
2	1	topontopi	$⊢ ordTop (\leq) \in Top$