What are the eigenvalues of the matrix with rows (2, -3) and (0, 6)?
Answer and explanation
Correct answer: D. 2 and 6
- Step 1: The matrix is upper triangular, so the eigenvalues are the diagonal entries. Step 2. They are 2 and 6. Answer: 2 and 6. Why not the others: 8 and 12 is what you get if you give the trace and the determinant. -2 and -6 is what you get if you change the signs of the diagonal. 2 and -3 is what you get if you use a diagonal entry and the off-diagonal entry.
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