Question

Himpunanpenyelesaianpersamaan 2cos^2x – 3cos x + 1 = 0 untuk 0 < x < 2πadalah .... a.{π/6,5π/6} b. {π/6,11π/6} c. {π/3,2π/3} d. {π/3,5π/3} e. {( 2π)/3,4π/3}

Answer 1

2 cos² x - 3 cos x  + 1 = 0
(2 cos x - 1)(cos x - 1) = 0
2 cos x - 1 = 0
cos x =
cos x = cos
x =
k = 0 ==> x =
atau
x =
k = 0 ==> x = (tdk memenuhi)
k = 1 ==> x =

HP = {}