Question

A) sin^2 x = 1
B) Cos^2 x = 25
C) 2 sin^2 x = 1
D) 8 cos^2 x-4 = 0

Answer 1

A)
sin²x = 1
sin x = 1 ∨ sin x = −1
x = 90° ∨ x = 270°

B)
cos²x = 25
cos x = 5 ∨ cos x = −5
Tidak ada nilai x ∈ R yang memenuhi

C)
2sin²x = 1
sin²x = ½
sin x = ½√2 ∨ sin x = −½√2
x = 45°, 135° ∨ x = 225°, 315°

D)
8cos²x − 4 = 0
8cos²x = 4
cos²x = ½
cos x = ½√2 ∨ cos x = −½√2
x = 45°, 315° ∨ x = 135°, 225°