<span>5sin3x - 9sin x = 0</span>
5(3sinx - 4sin^3 x) - 9sinx = 0
15sinx - 20sin^3 x - 9 sinx = 0
6sinx - 20sin^3 x = 02sinx (3 -10sin^2 x) = 0a) 2sinx = 0
sinx = 0 x1= πnб) 3 - 10sin^2 x = 0
10sin^2x = 3sin^2x = 3/10sinx = +-√(3/10)
sinx = √(3/10)x2 = (-1)^n * arcsin(3/10)+πn
sinx = -√(3/10)x3 = (-1)^(n+1) * arcsin(3/10)+πn