Question

show that sin A = Sin18˚ is a root of the equation
4 sin^2 A + 2 sin A - 1 = 0

Answer 1

This is going to be a little complicated.
Ready?

Answer 2

Complicated??

Answer 3

@waterineyes I try to assume everyone is a beginner.

Answer 4

No. I did not mean that..

I mean when you are there, then how it can become Complicated??