Question

Encontrar o valor de X tal que cos x +1 = sen²x

Answer 1

cos x + 1 = sen² x
cos x - sen² x = - 1
cos x - (1 - cos² x) = - 1
cos x - 1 + cos² x = - 1
cos² x + cos x = 0
cos x(cos x + 1) = 0

cos x = 0

cos x + 1 = 0
cos x = - 1

cos 180° = - 1

x = a + 2kπ
x = π + 2kπ