Решите уавнение 2cos x/2+1=0

Question

Решите уавнение 2cos x/2+1=0

Answer 1

2cos(x/2)=-1
Cos(x/2)=-1/2
x/2=±Π/3+2Πk
x=±2Π/3 + 4Πk

Answer 2

1)2cos(x/2)=-1;
2)cos(x/2)=-1/2;
3)x/2=±Π/3+2Πk;
4)x=±2Π/3 + 4Πk.