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Metamath Proof Explorer


Theorem sinhalfpi

Description: The sine of _pi / 2 is 1. (Contributed by Paul Chapman, 23-Jan-2008)

Ref Expression
Assertion sinhalfpi ( sin ‘ ( π / 2 ) ) = 1

Proof

Step Hyp Ref Expression
1 sinhalfpilem ( ( sin ‘ ( π / 2 ) ) = 1 ∧ ( cos ‘ ( π / 2 ) ) = 0 )
2 1 simpli ( sin ‘ ( π / 2 ) ) = 1