Penyelesaian dari trigonometri sederhana, tan 2x : -1/3√3 ?

tan 2x = -1/3 akar3
tan 2x = tan (-30)

2x = -30 + k.180
x = -15 + k.90
k = 1, x = 75°
k = 2, x = 165°
k = 3, x = 255°
k = 4, x = 345°

Hp = {75° , 165° , 255° , 345°}