Khan Academy: Graphs of Trig Functions: Example: Intersection of Sine and Cosine

Calculators ... they are more efficient than tables. Using two 30-60 right triangles, the segment of a playlist on geometry shows that trigonometric ratios for an angle are the same independent of the size of the triangle. The video...

Sal takes the mystery out of the trigonometric identities by showing how easily they can be derived. He continues with a problem he started in the video �Trig Identities part three (part five if you watch the proofs) and proves the trig...

SOH, what is this thing called trigonometric ratios? A section of an extensive playlist on geometry identifies the adjacent and opposite sides in relationship of an angle. Using the identified sides, the video defines the sine, cosine,...

Basic interpretation of the graph of the cosine function

Video shows solving an equation with sine and cosine by using a trigonometric identity and solving the resulting quadratic equation. [10:01]

Continuation of video lesson using the basic trigonometric functions to determine unknown side lengths of a right triangle. Example shows using trigonometry as well as the Pythagorean Theorem to find the length of the third side of the...

Video using the basic trigonometric functions to find the length of a side in a right triangle. Examples are given with angle measures in radians. Includes link to additional practice problems. [10:03]

Analyzing the amplitude and periods of the sine and cosine functions.

Determining the equations of trig functions by inspecting their graphs.

A video graphing a sin curve to think about its domain and range.