Theorem letopuni

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

	Ref	Expression
Assertion	letopuni	$$⊢{ℝ}^{*}=\bigcup \mathrm{ordTop}\left(\le \right)$$

Proof

Step	Hyp	Ref	Expression
1		letopon	$$⊢\mathrm{ordTop}\left(\le \right)\in \mathrm{TopOn}\left({ℝ}^{*}\right)$$
2	1	toponunii	$$⊢{ℝ}^{*}=\bigcup \mathrm{ordTop}\left(\le \right)$$