Question

Решите уравнение: sinx/2*sin3x/2=1/2

Answer 1

cosx-cos2x=1

cosx-(2cos^2x-1)=1

cosx-2cos^2x=0

cosx=0

x=П/2(2k+1)

1=2cosx

cox=1/2

x=+-П/3+2Пk