Jika tan x = 2 dengan A terletak di kuadran III, maka hitunglah nilai dari

Tan x = 2

depan = -2
samping = -1
miring = √5

sin x = -2√5/5
cos x = -√5/5

= {sin(180 – x) – sin(90 – x)} / {cos(90 + x) + cos(180 – x)}
= (sin x – cos x) / -cos x – cos x
= -√5/5 / √5/5
= -1