or, How to Remember Trigonometric Identities
Copyright � 1997�2025 by Stan Brown, BrownMath.com
Summary: Faced with the large number of trigonometric identities, students tend to try to memorize them all. That way lies disaster. When you memorize a formula by rote, you have no way to know whether you�re remembering it correctly. I believe it is much more effective (and, in the long run, much easier) to understand thoroughly how the trig functions work, memorize half a dozen formulas, and work out the rest as needed. That�s what these pages show you how to do.
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