Question

If 2cos θ=√3, prove that 3sin θ-4sin3θ=1​

Answer 1

Answer:

2cosθ= √3

⇒cosθ=√3/2

⇒θ=30°

⇒3sinθ−4sin 3

θ=sin3θ[∴sin3θ=3sin3θ−4sin 3⁰]

=sin(3×30°)

=sin90°

=1

Hence, the answer is 1.