Hasil dari Tan 2x : -1/2√3 dalam persamaan trigonometri sederhana ?

tan 2x = (-1/2) akar3
tan 2x = tan (-40,9)

2x = -40,9 + k.180°
x = -20,45 + k.90°

k = 1, x = 69,55°
k = 2, x = 159,55°
k = 3, x = 249,55°
k = 4, x = 339,55°

HP = {69,55°, 159,55°, 249,55°, 339,55°}