Khan Academy on a Stick
Example: Using the unit circle definition of trig functions
Worked example using our knowledge of 30-60-90 triangles and similarity to evaluate tan, cos and sin.
If the above player doesn't work, you can try this direct link.
Worked example using our knowledge of 30-60-90 triangles and similarity to evaluate tan, cos and sin.
If the above player doesn't work, you can try this direct link.