Question

2 cos(п/5+х)sin(п/5+х)=1/2

Answer 1

2cos(π/5+x) sin(π/5+x)=1/2

sin(2π/5+2x)=1/2

2π/5+2x=(-1)^n *π/6+πn , n∈Z

2x=(-1)^n*π/6-2π/5+πn , n∈Z

x=(-1)^n *π/12-π/5+πn/2 , n∈Z