SOLUTION: If A + B + C = 180 then prove that Cos^2 A + cos^2 B + 2cosAcosBcosC=sin^2 C

SOLUTION: If A + B + C = 180 then prove that Cos^2 A + cos^2 B + 2cosAcosBcosC=sin^2 C

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Question 1046463: If A + B + C = 180 then prove that
Cos^2 A + cos^2 B + 2cosAcosBcosC=sin^2 C
Answer by robertb(5830) (Show Source): You can put this solution on YOUR website!

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