Question

HELP. Jika sin^2 x = akar 3 . cos x, maka cos x = ?

^ = pangkat

Answer 1

Sin² x = √3. cos x
1- cos² x  - √3 cos x = 0 atau
cos² x + √3. cos x  = 1
(cos x + 1/2√3)² = 1 + 3/4 = 7/4
(cos x + 1/2 √3) = 1/2 √7

cos x = -1/2 √3 + 1/2 √7 = 1/2 (√7 - √3)
cos x = -1/2 √3 - 1/2 √7 = -1/2(√7  +√3)