## The Unit Circle

The Unit Circle is perhaps the single most important thing to understand about Trigonometry.  Sure, you can rely on a calculator to get some answers, but sometimes calculators don’t consider all of the possibilities.  If you understand the Unit Circle, you will.

The Unit Circle will help you understand how to find the sine, cosine, or tangent, of an angle greater than 90 degrees, help you find tangent of things like 90 degrees (which seems impossible because tangent is opposite over adjacent), and is a great reference for finding common Trigonometric values.

The Unit Circle is constructed from a pair of special right triangles.  This is why we consider knowledge of those triangles analogous to arithmetic.  It all starts with the 30 – 60 – 90 and 45 – 45 – 90 right triangles!

Read through the notes, taking notes yourself.  Download the PowerPoint and play it.  Give yourself the patience required to understand the information.  Watch the video, then try the practice problems.

If you have questions or confusion about the Unit Circle, please send an email with your question.  Send emails to:  [email protected].