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arXiv · 2106.13595

Two eigenvectors for the price of one

Juan Tolosa
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Abstract

Starting from a mistake done by a student, we discover an unexpected method of finding both eigenvectors for a $2\times2$ matrix with distinct eigenvalues in a single computation. We discuss a connection with the Cayley-Hamilton theorem, and show the corresponding generalization for a $3 \times 3$ matrix. The arguments should be understandable for strong linear algebra students.

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Juan Tolosa. 2021-06-21. Two eigenvectors for the price of one. https://arxiv.org/abs/2106.13595

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