Question

How do you find the exact value of cos 180degrees - sin 180degrees?

Answer 1

`-1`

Explanation:

Within the unit circle, cosine provides the `x` coordinate of a point on the surface of the circle. Sine provides the `y` coordinate of a point on the surface of the circle.

At `180^o`, the point on the unit circle surface is `(-1,0)`. So this means:

`x=cos(180^o) = -1`

`y=sin(180^o) = 0`

To find the exact value of `cos(180^o) -sin(180^o)`

`-1 - 0 = -1`