General Mathematics

    

New Tricks for Memorizing Trigonometric Identities

Authors: Timothy Jones

We give a way to memorize all 27 standard trigonometric identities, including the product to sum (P2S) and sum to product (S2P) trigonometric identities. These are generally not memorized, but puzzled out using the sum of two angles for the P2S and then P2S for S2P. We show here a faster way to recall these using what might be called heuristic generalizations. All 27 of the standard identities are reviewed in light of this type of trick. Links to a TI-84 program and a youtube video are given.

Comments: 7 Pages. Received some suggestions that are reflected here.

Download: PDF

Submission history

[v1] 2025-01-31 12:57:38
[v2] 2025-02-10 11:05:56
[v3] 2025-04-08 11:54:02

Unique-IP document downloads: 627 times

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