How do you find the exact value of arc tan(-sqrt3)?

1 Answer
May 14, 2015

sin(pi/3) = sqrt(3)/2 and cos(pi/3) = 1/2

Since sin(-theta) = -sin theta and cos(-theta) = cos theta for any theta, we have

tan(-pi/3) = sin(-pi/3)/cos(-pi/3) = (-sin(pi/3))/cos(pi/3)

= -(sqrt(3)/2)/(1/2) = -sqrt(3)/1 = -sqrt(3)

So arctan(-sqrt(3)) = -pi/3