Question

sinx+(cosx/2-sinx/2)(cosx/2+sinx/2)=0

Answer 1

sinx+(cos²x/2-sin²x/2)=0
sinx+cosx=0
sinx+sin(π/2-x)=0
2sinπ/4cos(x-π/4)=0
cos(x-π/4)=0
x-π/4=π/2+πn
x=π/4+π/2+πn
x=3π/4+πn