What is the unit circle?
The unit circle is a circle with a radius of 1, centered at the spot (0,0) on a graph. It’s a key tool in trigonometry and precalculus. But to really use it, you have to know how to fill in the unit circle completely.
Filling it in means figuring out the (x, y) coordinates and the angles (in degrees and radians) at certain key points around the circle. When you’re done, you’ll have a quick visual reference for trigonometric values.
We’ll walk you through how to find the angles (in degrees and radians) and the (x, y) coordinates that go with them. Then, we’ll touch on how all of this relates to trigonometric functions.