Wolfram|Alpha is a great resource for finding the eigenvalues of matrices. You can also explore eigenvectors, characteristic polynomials, invertible matrices, diagonalization and many other matrix-related topics.
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Online Eigenvalue Calculator
Compute eigenvalues with Wolfram|Alpha
More than just an online eigenvalue calculator
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Tips for entering queries
Use plain English or common mathematical syntax to enter your queries. To enter a matrix, separate elements with commas and rows with curly braces, brackets or parentheses.
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