Question

2sin^2x=3cosx помогите срочно

Answer 1

2sin²x = 3cosx
2(1–cos²x) = 3 cosx
пусть соsx = c , |c |≤ 1
2 – 2c² = 3c
2c²+3c–2 = 0
c = – 4/2 ( |4/2| > 1)
c = 1/2

cosx = 1/2
x = π/3 + 2πn , n€Z
x = -π/3 + 2πk , k€Z