Question

cos2x=1 решите уравнение

Answer 1

cos2x = 1
2x = 2πn, n∈Z
x = πn, n∈Z

Answer 2

cos2x = 1
2x = +- arccos1 + 2Пn, n∈Z
2x = 0 + 2Пn, n∈Z
x = 2Пn/2, n∈Z
x = Пn, n∈Z

Ответ: x = Пn, n∈Z