Jawabanmu

2014-06-02T07:48:50+07:00
A(4, 120°)
Kartesius:
x = r cos a = 4 cos 120 = 4 . (-1/2) = -2
y = r sin a = 4 sin 120 = 4 . (1/2 √3) = 2√3
jadi, koordinatnya (x, y) = (-2, -2√3)