Sin(2x-п/2)=-1/2
принадлежащие промежутку:
(0;3п/2)

sin(2x-π/2)=-1/2sin(-(π/2-2x)=-1/2-sin(π/2-2x)=-1/2sin(π/2-2x)=1/2cos2x=1/22x=π/3+2πnх=π/6+πnх∈(0;3π/2)  ⇒х₁=π/6  x₂=7π/6.