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arXiv · 2607.10121

OFFER (One-Figure-Facilitates-Every-Relationship)for Trigonometric Functions

Samuel S. P. Shen
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Abstract

This article describes an approach that uses a single figure to illustrate all six trigonometric functions, their fundamental identities, and the law of cosines. We name this method OFFER (one-figure-facilitates-every-relationship) for the convenience of mathematics teaching. The article also describes the SPORT (story-picture-observe-review-tell) approach to effective mathematics learning.

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Samuel S. P. Shen. 2026-07-11. OFFER (One-Figure-Facilitates-Every-Relationship)for Trigonometric Functions. https://arxiv.org/abs/2607.10121

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