Решите уравнение -sinx/2=cosx
-sin(x/2) = cos x = 1 - 2sin^2(x/2) Замена sin(x/2) = y 2y^2 - y - 1 = 0 (y - 1)(2y + 1) = 0 y1 = sin(x/2) = -1/2 x/2 = -pi/6 + 2pi*k; x1 = -pi/3 + 4pi*k x/2 = -5pi/6 + 2pi*k; x2 = -5pi/3 + 4pi*k y2 = sin(x/2) = 1 x3 = pi/2 + 2pi*n