In quadrant II
cos θ = - 1 / 2
for
θ = 2 π / 3 rad (120°)
sin θ = sin 2 π / 3
sin θ = √3 / 2
tan θ = sin θ / cos θ = ( √3 / 2 ) / ( - 1 / 2 ) = - √3
Find tan0 if cos0= -1/2 and 0 terminates in quadrant II
2 answers
Cos A = x/r = -1/2
x^2 + y^2 = r^2
(-1)^2 + y^2 = 2^2
Y = sqrt3.
Tan A = y/x = sqrt3/-1 = -sqrt3.
x^2 + y^2 = r^2
(-1)^2 + y^2 = 2^2
Y = sqrt3.
Tan A = y/x = sqrt3/-1 = -sqrt3.