Question

Resolva a inequação Sen²x≥1/4 com 0 ≤x ≤2π

Answer 1

sen² x ≥ 1/4
sen² x = 1/4
sen x = 1/√4
sen x = √4/4 = 1/2

sen x = 1/2

sen x = - 1/2

x = a + 2kπ
x = π/6 + 2kπ

x = a + 2kπ
x = π - π/6 + 2kπ
x = 5π/6

sen x = - 1/2

x = a + 2kπ
x = π + π/6 + 2kπ
x = 7π/6 + 2kπ

x = a + 2kπ
x = 2π - π/6 + 2kπ
x = 11π/6 + 2kπ

S = {π/6, 5π/6, 7π/6, 11π/6}