Question20 Consider the matrix [math]. What are the eigenvalues of this matrix?Select one alternative: 1 and 5 1 and 6 0 and 5 0 and 6 ResetMaximum marks: 1 Flag question undefined

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Question20 Consider the matrix [math]. What are the eigenvalues of this matrix?Select one alternative: 1 and 5  1 and 6  0 and 5  0 and 6  ResetMaximum marks: 1 Flag question undefined

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First, I’ll restate the problem and the choices to make sure we’re oriented correctly.
Question: Consider the matrix [math]. What are the eigenvalues of this matrix? Select one alternative:
- 1 and 5
- 1 and 6
- 0 and 5
- 0 and 6

Option 1: 1 and 5
This choice asserts that the two eigenvalues are 1 and 5. To evaluate this, recall two fundamental facts about eigenvalues of a square matrix: (a) the sum of the eigenvalues (counting multiplicities) equals the trace of the matrix, and (b) the product of the eigenvalues (counting multiplicities) equals the determinant of the matrix. Without the actual matrix, we cannot confirm whether 1 + 5 = trace and 1 × 5 = determinant hold. If the matrix had a trace of 6 and a determinant of 5, this pair would be consistent; otherwise it would not. In general, we would also consider the characteristic polynomial and whether 1 and 5 are indeed roots, which would require substituting the matrix into (A − λI) and solving det(A − λI) = 0.

Option 2: 1 and 6
Here, the claimed eigenvalues are 1 and 6. Again, verification relies on the trace being 1 + 6 = 7 and the determinant being 1 × 6 = 6. If the matrix’s trace is 7 and determinant is 6, this option would fit with the basic eigenvalue relationships. Absent A, we cannot confirm this alignment. The characteristic polynomial approach would also need to show that λ = 1 and λ = 6 are the roots, which entails det(A − I) = 0 and det(A − 6I) = 0.

Option 3: 0 and 5
This option proposes eigenvalues 0 and 5. In this case, the trace would be 0 + 5 = 5 and the determinant would be 0 × 5 = 0. A determinant of zero would indicate that the matrix is singular (not invertible), and a trace of 5 would need to be consistent with the given matrix. If the matrix is indeed singular and has trace 5, this pair could be plausible; otherwise it would not be.

Option 4: 0 and 6
This option suggests eigenvalues 0 and 6. The trace would be 0 + 6 = 6, and the determinant would be 0 × 6 = 0. Like the previous case, a zero determinant implies the matrix is singular. If the matrix has trace 6 and is singular, this pair would be consistent with those two basic properties. If the actual trace or determinant differ, this set would be incorrect.

General reasoning and potential pitfalls:
- Remember that eigenvalues come from solving det(A − λI) = 0. Each eigenvalue λ makes (A − λI) singular, meaning det(A − λI) = 0. The full set of eigenvalues corresponds to all roots of the characteristic polynomial.
- The trace of A equals the sum of all eigenvalues (including multiplicities). This gives a quick consistency check: any proposed pair must sum to the matrix’s trace if the matrix is 2×2.
- The determinant of A equals the product of the eigenvalues. This provides another quick check: any proposed pair must multiply to the determinant.
- Without the explicit matrix A or at least its trace and determinant, we cannot decisively determine which pair is correct. Different 2×2 matrices can share the same trace and determinant but have different eigenvalues if multiplicities or higher-dimensional considerations are involved; however, for 2×2 matrices, the pair of eigenvalues (counting multiplicities) is determined by the trace and determinant.

If the actual matrix A were provided, the steps to identify the correct pair would be:
- Compute the trace tr(A) and determinant det(A).
- Check which pair (λ1, λ2) satisfies λ1 + λ2 = tr(A) and λ1 × λ2 = det(A).
- Optionally, compute det(A − I) and det(A − 6I) or directly solve the characteristic polynomial to verify which eigenvalues are roots.

Because the matrix [math] is not specified here, we cannot definitively determine which of the four options corresponds to the actual eigenvalues. The correct choice would be the pair whose sum equals the matrix’s trace and whose product equals the determinant, as verified via the characteristic polynomial or determinant tests.

Question20 Consider the matrix [math]. What are the eigenvalues of this matrix?Select one alternative: 1 and 5 1 and 6 0 and 5 0 and 6 ResetMaximum marks: 1 Flag question undefined

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