# What is the Cartesian form of ( -13 , (16pi)/6 ) ?

Apr 21, 2017

$x = r \cos \theta$
$y = r \sin \theta$
$\sin \left(\frac{16}{6} \pi\right) = \frac{\sqrt{3}}{2}$
$\cos \left(\frac{16}{6} \pi\right) = - \frac{1}{2}$
$\left(x , y\right) = \left(- \frac{13}{2} , - 13 \frac{\sqrt{3}}{2}\right)$

#### Explanation:

Use the formula to calculate
By the definition