Question

Solve sin2x + 2sinx = 0 for 0 ≤ x < 2π. ...?

Answer 1

Sin 2 x + 2 sin x = 0
2 sin x cos x + 2 sin x = 0 / : 2
sin x cos x + sin x = 0
sin x ( cos x + 1 ) = 0
sin x = 0,  cos x + 1 = 0,  cos x = - 1;
Answer:
x = 0,  or x = π