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Thursday, April 11, 2013

Proving Trigonometric Identities, 4

Category: Trigonometry

"Published in Newark, California, USA"

If A + B + C = 180°, prove that


Consider the given equation above

In proving of trigonometric identities, we have to choose first the more complicated part and then simplify until it match with the other side of the equation. In this case, we have to choose the right side of the equation as follows

Use the Sum and Product Formula, we have


Therefore, the above equation becomes

Therefore, the identity is correct for