MathDB

B4

Part of 1956 Putnam

Problems(1)

Putnam 1956 B4

Source: Putnam 1956

7/5/2022
Prove that if A,B,A,B, and CC are angles of a triangle measured in radians then Acos⁡B+sin⁡Acos⁡C>0.A \cos B +\sin A \cos C >0.
Putnamtrigonometryinequalities