You are here

Complex Eigenvalues and Rotations: Are Your Students Going in Circles?

by James Duemmel (Western Washington University)

This article originally appeared in:
College Mathematics Journal
November, 1996

Subject classification(s): Algebra and Number Theory | Linear Algebra | Eigenvalues and Eigenvectors
Applicable Course(s): 3.8 Linear/Matrix Algebra

The author shows that every \(2 \times 2\) real matrix with nonreal eigenvalues represents the composition of the following three operations: (1) a vertical “lift” to a plane through the origin, (2) a rotation in that plane, and (3) a “drop” back into the \(x-y\)-plane.


A pdf copy of the article can be viewed by clicking below. Since the copy is a faithful reproduction of the actual journal pages, the article may not begin at the top of the first page.

To open this file please click here.

These pdf files are furnished by JSTOR.

Classroom Capsules would not be possible without the contribution of JSTOR.

JSTOR provides online access to pdf copies of 512 journals, including all three print journals of the Mathematical Association of America: The American Mathematical Monthly, College Mathematics Journal, and Mathematics Magazine. We are grateful for JSTOR's cooperation in providing the pdf pages that we are using for Classroom Capsules.

Capsule Course Topic(s):
Linear Algebra | Eigenvalues and Eigenvectors
Average: 3.1 (25 votes)