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Metamath Proof Explorer

Theorem sinpi

Description: The sine of _pi is 0. (Contributed by Paul Chapman, 23-Jan-2008)

Ref Expression
Assertion sinpi ( sin ‘ π ) = 0

Proof

Step Hyp Ref Expression
1 pilem3 ⊢ ( π ∈ ( 2 (,) 4 ) ∧ ( sin ‘ π ) = 0 )
2 1 simpri ⊢ ( sin ‘ π ) = 0