Before we start graphing sine and cosine we must first take a look at the unit circle. Find the numbers that are located in parenthesis around the circle. These numbers are the x and y coordinates for points on a graph. If you need help figuring out how we get these numbers check out this website:
http://www.mathvids.com/lesson/mathhelp/36-unit-circleThe right number inside the parenthesis is the value of sine (y-value) for that angle.
The left number inside the parenthesis is the value of cosine (y-value) for that angle.
The number in blue is the x-value on the sine or cosine graph.We will explain more in the next pages...