Sal finds trigonometric identities for sine and cosine by considering angle rotations on the unit circle. [6:13]

Sal solves a problem by considering the periodicity of the tangent function. [4:01]

In this teacher-created video, trigonometric functions are developed and explored by changing one of the angles in a right triangle. [10:57]

Produced by a teacher at a school in Jacksonville, FL, this video discusses whether the six trig functions are odd or even functions. [7:14]

The video from Khan Academy provides practice questions for the SAT. Watch Sal work through a harder angles, arc lengths, and trig functions problem.

The video from Khan Academy provides practice questions for the SAT. Students will watch Sal work through a basic angles, arc lengths, and trig functions problem.