What are the eigenvalues of the matrix with rows (6, -4) and (0, 5)?
Answer and explanation
Correct answer: A. 5 and 6
- Step 1: The matrix is upper triangular, so the eigenvalues are the diagonal entries. Step 2. They are 6 and 5. Answer: 5 and 6. Why not the others: 11 and 30 is what you get if you give the trace and the determinant. -6 and -5 is what you get if you change the signs of the diagonal. 6 and -4 is what you get if you use a diagonal entry and the off-diagonal entry.
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