Question

The measure θ of an angle in standard position is given. Find the exact values of cos θ and sin θ for the angle measure:

Answer 1

sin(2pi/3) = sqrt(3)/2

cos(2pi/3) = -1/2

Explanation:

2pi/3 lies in the second quadrant with basic angle: pi - 2pi/3 = pi/3

sin(pi/3) = sqrt(3)/2

cos(pi/3) = 1/2

In the second quadrant, sin is positive and cos is negative

Therefore,

sin(2pi/3) = sqrt(3)/2

cos(2pi/3) = -1/2

Answer 2

cosθ = -1/2, sinθ =
`√(3) /2`

Explanation: