→ Trig without Tears

Trig without Tears

or, How to Remember Trigonometric Identities

Copyright © 1997–2017 Stan Brown,

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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start:  1/Intro

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