Master Evaluating the double angle for Sine, Cosine and Tagent, given an equation and constraint

The video tutorial explains how to evaluate double angles for sine, cosine, and tangent when given a cosine equation and a constraint that the angle is in the third quadrant. It covers drawing the right triangle, using the Pythagorean theorem, and applying formulas to calculate the double angles.

How do you derive the cosine of two Theta using the values obtained from the triangle?

What steps are involved in calculating the tangent of two Theta?

Summarize the overall process of evaluating the double angle for sine, cosine, and tangent given an equation and an angle.