481. sin(x+π/6)+ +cos(x-π/6)=0.

sin(x+π/6)+cos(x-π/6)=0

sin(x+π/6)+sin(π/2-(x-π/6))=0

sin(x+π/6)+sin(2π/3-x)=0

2sin((x+π/6+2π/3-x)/2)cos((x+π/6-2π/3+x)/2)=0

2sin(5π/12)cos(x-π/4)=0

cos(x-π/4)=0

x-π/4=π/2+πn, n∈Z

x=3π/4+πn, n∈Z

Ответ: x=3π/4+πn, n∈Z