Решите уравнение cosx+√2\2=0

Question

Решите уравнение cosx+√2\2=0

Answer 1

Cosx=-√2/2
x=+-3π/4+2πk, k∈Z

Answer 2

Cosx + √2/2 = 0
cosx = -√2/2
x = +-arccos(-√2/2) + 2πn, n ∈ Z
х = +-3π/4 + 2πn, n ∈ Z