In this lesson, we learn how to use trig identities to make computations. Specifically, we are given the cosine of A and are asked to find the sine of 2A and the cosine of A over 2. The problem is solved by drawing a picture and using the formula for the sine of 2A, which is 2 sine A cosine A. We also use a formula for the cosine of A over 2 and solve a complex fraction to find the answer. This lesson provides helpful examples for using trig identities to solve problems.
Using Trig Identities to make computations.
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