Question

Тригонометрия.
Помогите пожалуйста
1) sin(x/2+П/8)=0
2) cos(5x-8)=-1

Answer 1

1) sin(x/2+π/8)=0
x/2+π/8=πk, k∈Z
x/2=πk-π/8
x=2πk-π/4   ,     k∈Z

2) cos(5x-8) = - 1
    5x-8=π+2πk,   k∈Z
    5x=8+π+2πk
     x=π/5+2πk/5+1,6;    k∈Z