Question

If x=30° verify
Cos3x= 4cos(cube)x — 3cosx

Answer 1

Step-by-step explanation:

x=30

cos3x=4cos(cube)x-3cosx. (cos30=√3/2)

as x=30 3x=90

cos90=4cos(cube)30-3cos30

0=(4×3√3)/8-3√3/2

0=(3√3)/2-(3√3)/2

0=0

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