Question

Tentukan Himpunan Penyelesaian dari. . .
a) 2 cos 3x - √3 = 0
b) tan (2x + 30) - 1 = 0

Answer 1

2 cos 3x - √3 = 0
2 cos 3x = √3
cos 3x =
cos 3x = cos 30
3x = 30 + k.360
x = 10 + k.120
k = 0, x = 10
k = 1, x = 130
k = 2, x = 250
atau
3x = -30 + k.360
x = -10 + k.120
k = 1, x = 110
k = 2, x = 230
k = 3, x = 350

tan(2x + 30) - 1 = 0
tan(2x + 30) = 1
tan(2x + 30) = tan 45
2x + 30 = 45 + k.180
2x = 15 + k.180
x = 7.5 + k.90
k = 0, x = 7.5
k = 1, x = 97.5
k = 2, x = 187.5
k = 3, x = 277.5