Question

HP dari 2sin^2x+3cos x=0 0<×<360 adalah...

Answer 1

Sin^2 (x)= 1-cos^2 (x)

2 sin^2 x + 3 cos x = 0
2 (1-cos^2 x) + 3 cos x = 0
2- 2 cos^2 x + 3 cos x = 0
-2 cos^2 x + 3 cos x + 2= 0
2 cos^2 x - 3 cos x - 2 = 0
(2 cos x + 1)(cos x - 2) = 0

1)... cos x = -1/2 -> (x=120,240)
2)... cos x = 2 ( tidak dianggap)

hp: {120,240}