-2sin(x+n/4)=корень 3

-2sin(x+π/4)=√3

sin(x+π/4)=√3/2

x+π/4=π/3+2πn

x+π/4=2π/3+2πn

x=π/3-π/4+2πn

x=2π/3-π/4+2πn

x=π/12+2πn

x=5π/12+2πn, n принадл. Z.