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arXiv · 2201.07743

Conway's Nightmare: Brahmagupta and Butterflies

Richard Evan Schwartz
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Abstract

This note gives a very succinct conceptual proof of Brahmagupta's formula for cyclic quadrilaterals, and then a long discussion about how the proof is inspired by ideas from modern mathematics.

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Richard Evan Schwartz. 2022-01-19. Conway's Nightmare: Brahmagupta and Butterflies. https://arxiv.org/abs/2201.07743

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