Theorem letop

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

	Ref	Expression
Assertion	letop	⊢ ( ordTop ‘ ≤ ) ∈ Top

Proof

Step	Hyp	Ref	Expression
1		letopon	⊢ ( ordTop ‘ ≤ ) ∈ ( TopOn ‘ ℝ* )
2	1	topontopi	⊢ ( ordTop ‘ ≤ ) ∈ Top