Metamath Proof Explorer

Theorem letopuni

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

Ref Expression
Assertion letopuni 
|- RR* = U. ( ordTop ` <_ )

Proof

Step Hyp Ref Expression
1 letopon 
 |-  ( ordTop ` <_ ) e. ( TopOn ` RR* )
2 1 toponunii 
 |-  RR* = U. ( ordTop ` <_ )