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Prove that cos 48^(@) . Cos 12^(@) =(3+s...

Prove that `cos 48^(@) . Cos 12^(@) =(3+sqrt5)/(8)`.

Text Solution

Verified by Experts

The correct Answer is:
`=(1)/(2)[(2+sqrt5+1)/(4)]=(3+sqrt5)/(8)=R.H.S`
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