1.

If A + B + C = π, Prove that cos 4A + cos 4B + cos 4C = -1 + 4 cos 2A cos 2B cos 2C.

Answer»

If A + B + C = π, Prove that

cos 4A + cos 4B + cos 4C = -1 + 4 cos 2A cos 2B cos 2C.



Discussion

No Comment Found