Sin(5п-x)=cos(2x+7п)

sin * (5 - x) = cos * (2x + 7);

sin * (5 - x) = -cos * (7 - 2x);

sinx = cos2x;

sinx = cos^2 x - sin^2 x;

sinx = 1 - sin^2 x - sin^2 x;

sinx = 1 - 2sin^2 x;

2sin^2 x + sinx - 1 = 0;

D = 1 + 4* 2 = 9;

x1 = -1 - подходит;

x2 = 2 - не подходит;

Sin(x) = -1;

х = -П/2 + 2Пn, nZ.