# Trig without Tears

or, How to Remember Trigonometric Identities

revised 4 Apr 2016

Copyright © 1997–2016 Stan Brown, BrownMath.com

or, How to Remember Trigonometric Identities

revised 4 Apr 2016

Copyright © 1997–2016 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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start: 1/Introduction

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Updates and new info: http://BrownMath.com/twt/