25sin^x+30sincosx+9cos^x=0
в квадрате?
подправь уравнение.
9 cos^2x
25sin²x + 30 sinx cos x + 9cos²x = 0 (5sin x + 3cos x)² = 0 5sin x + 3cos x = 0 |:cos x≠0 5tg x + 3 = 0 tg x = -3/5 x=-arctg(3/5) + πn,n ∈ Z
cgc
спс