Question

Hitunglah nilai dari :
a. sin (-45 drajat)
b. tan (-240 drajat)
c .cos (-135 drajat)
d. sin (-225 drajat)
e. cotan (-120 drajat)

Answer 1

A. sin(-45) = - sin 45 = -1/2 √2
b. tan(-240) = - tan 240 = - tan(180 + 60) = - tan 60 = -√3
c. cos(-135) = cos 135 = cos(180-45) = - cos 45 = -1/2√2
d. sin(-225) = - sin 225 = - sin(180+45) = sin 45 = 1/2√2
e. cotan(-120) = - cotan 120 = - cotan(180 - 60) = cotan 60 = 1/3√3