помогиииите. sinx - 2cos(квадрат)х= sin3x -1

Ответ. sin(x)-2*(cos(x))^2=sin(3*x)-1; 1-2*(cos(x))^2=sin(3*x)-sin(x); (sin(x))^2-(cos(x))^2=2*cos(2*x)*sin(x);
(sin(x))^2-(cos(x))^2-4*((cos(x))^2-(sin(x))^2)*sin(x)=0; ((sin(x))^2-(cos(x))^2)*(1-4*sin(x))=0; sin(x1)=0,25;
2*(sin(x))^2-1=0; sin(x2)=1/(2^0,5); sin(x3)=-1/(2^0,5);