Question

hello can you help me with this plane trigonometry question please and thank you for putting the time for explaining this to me and I thank you for your time and for the question it has to be in exact value because it won't accept decimals

Answer 1

What you need to do is work using radians instead of using degrees.

$\sin (\frac{5\pi}{3})=-\frac{\sqrt[]{3}}{2}$$\cos (\frac{5\pi}{3})=\frac{1}{2}$

You could write the first one as:

$Cos(\frac{5\pi}{3})=\text{-}(3)^{(1/2)}/2$