In this lesson, Julie Harland demonstrates how to use trig identities to make computations. Using the formula for cosine of 2A and substituting the value of sine of A over 2, she shows how to find the value of cosine of A. She also emphasizes that every problem is different and requires a unique approach. To find the value of sine or tangent of A, she suggests using the Tha-Green theorem and understanding the quadrant in which A falls.
Using Trig Identities to make computations.
More free YouTube videos by Julie Harland are organized at http://yourmathgal.com