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Metamath Proof Explorer

Theorem neghalfpire

Description: -u _pi / 2 is real. (Contributed by David A. Wheeler, 8-Dec-2018)

Ref Expression
Assertion neghalfpire 
|- -u ( _pi / 2 ) e. RR

Proof

Step Hyp Ref Expression
1 halfpire 
 |-  ( _pi / 2 ) e. RR
2 1 renegcli 
 |-  -u ( _pi / 2 ) e. RR