5 sin 3x — 9 sin x=0 _________________________________________________

5sin3x — 9sin x=05 (3sinx — 4sin^3 x) — 9sinx=015sinx — 20sin^3 x — 9 sinx=06sinx — 20sin^3 x=02sinx (3 -10sin^2 x)=0a) 2sinx=0sinx=0 x1=πnб) 3 — 10sin^2 x=010sin^2x=3sin^2x=3/10sinx=+-√ (3/10) sinx=√ (3/10) x2=(-1) ^n*arcsin (3/10)+πnsinx=-√ (3/10) x3=(-1) ^ (n+1)*arcsin (3/10)+πn