# Determine the exact value of (trig function) given...

• February 18th 2010, 06:37 PM
Incursion
Determine the exact value of (trig function) given...
A coordinate plane, and a coordinate. An example is: Coordinate (-3, -5) in quadrant 3?
• February 18th 2010, 06:46 PM
Prove It
Quote:

Originally Posted by Incursion
A coordinate plane, and a coordinate. An example is: Coordinate (-3, -5) in quadrant 3?

$x = r\cos{\theta}$ and $y = r\sin{\theta}$

where $r = \sqrt{x^2 + y^2}$.