Question

Suppose that P is the point on the unit circle obtained by rotating the initial ray counterclockwise through 240°. Find the measure of the reference angle for 240°, and then find sin(240°) and cos(240°).

Answer 1

Explanation:

its already answered :(

Answer 2

Reference angle will be 60°

sin(240°)
`(-√(3))/(2)`

cos(240) =
`(1)/(2)`

Explanation:

We have given angle 240°

We ave t find the reference angle of 240°

As we know that 240° will lie in third quadrant

And for third quadrant reference angle is given by

Reference angle = angle - 180° =240°-180 = 60°

Now we have to find the value of sin(240°)

`sin(240^(\circ))=sin(180+60)=-sin60^(\circ)=(-√(3))/(2)`

Now
`cos(240^(\circ))=cos(180+60)=-cos60^(\circ)=\frac{-{1}}{2}`