Question

2 sin^2 x/2 + 3 sin x + 2 = 0

Answer 1

2 sin^2 x/2 + 3 sin x + 2 = 0
2 sin^2 x/2 + 6sinx/2*cosx/2=0
sin^2 x/2 + 3sinx/2*cosx/2=0
sinx/2=0   x/2=πk   x=2πk   k∈Z
sinx/2+3cosx/2=0
tgx/2=-3  x/2=-arctg3+πk  x=-2arctg3+2πk    k∈Z