Question

Find the value of 3sinx-4cos^3x.If sin x=1/2.

Answer 1

sinx = 1/2

x= 30

3 sin30 - 4cos³30

= 3/2 - 4(√3/2)³

= 3/2- 4(3√3/8)

= 3/2 - 3√3/2

= 3 - 3√3/2

= -1.09