Нужно полное решение! sin(x/4)cos(x/4)=-(1/4)

Sin(x/4)*cos(x/4)=-(1/4)
Sin(2x)=2*sinx*cosx,
Значит sinx*cosx=2*sinx*cosx /2 = sin(2x) /2,
Значит (2*sin(x/4)*cos(x/4))/2=-(1/4)
sin(2x/4)/2=-(1/4)
sin(x/2)=-0.5
|x/2=-π/6+2πk; k∈Z
|x/2=-5π/6+2πk; k∈Z