Ask Me Help Desk - Prove: cos^A/2 cos^2B/2 cos^2C/2=2 2sinA/2*sinB/2*sinC/2

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prove: cos^A/2 cos^2B/2 cos^2C/2=2 2sinA/2*sinB/2*sinC/2

Solve it ***!

If this is what you are trying to prove:

$\cos^2$\frac{A}{2}$\cos^2$\frac{B}{2}$\cos^2$ \frac{C}{2}$ \equiv 2 + 2\sin$\frac{A}{2}$\sin$\frac{A}{2}$\sin$\frac {A}{2}$$

I don't see how they are equivalent...

cos is always less than 1. Hence, the left hand side is less than 1.

On the right hand side, you have 2 + 2sin sin sin

sin is less than 1, and twice that isn't much... the '2' in front of everything makes it too much.

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