Question

(2sinx-1)*sqrt{cos(pi/4)+x}=0

Answer 1

2sinx-1=0
2sinx=1
sinx=1/2
x=(-1)^n*π/6+πn

cos(π/4+x)=0
π/4+x=π/2+πn
x=π/2-π/4+πn=π/4+πn