Question:

If $\alpha,\beta,\gamma$ are the roots of the equation $x^3+bx+c=0$, then \[ \begin{vmatrix} \alpha & \beta & \gamma\\ \beta & \gamma & \alpha\\ \gamma & \alpha & \beta \end{vmatrix} = \]

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If the sum of columns or rows becomes the zero vector, the determinant is zero.
Updated On: Jun 3, 2026
  • $-b^3$
  • $b^3-3c$
  • $b^2-3c$
  • $0$
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The Correct Option is D

Solution and Explanation

Step 1: Concept
A circulant determinant with rows obtained by cyclic permutation can be evaluated using row properties.

Step 2: Meaning
Since $\alpha,\beta,\gamma$ are roots of \[ x^3+bx+c=0, \] we have \[ \alpha+\beta+\gamma=0. \]

Step 3: Analysis
Adding all three columns gives \[ \begin{bmatrix} \alpha+\beta+\gamma\\ \alpha+\beta+\gamma\\ \alpha+\beta+\gamma \end{bmatrix} = \begin{bmatrix} 0\\0\\0 \end{bmatrix}. \] Thus the columns are linearly dependent.

Step 4: Conclusion
Therefore the determinant must be zero.

Final Answer: (D)
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