ПОМОГИТЕ!!!!!!!!!! sinx+sin2x+sin3x+sin4x=0

sinx+sin2x+sin3x+sin4x=0 (sinx+sin4x)+(sin2x+sin3x)=0 2sin(5x/2)cos(3x/2)+2sin(5x/2)cos(x/2)=0|:2 sin(5x/2)(cos(3x/2)+cos(x/2))=0 sin(5x/2)*2cos(x)*cos(x/2)=0 1) sin(5x/2)=0 5x/2=πn x=(2πn)/5,n∈Z. 2) cosx=0 x=(π/2)+πn,n∈Z. 3) cos(x/2)=0 x/2=(π/2)+πn x=π+2πn,n∈Z.