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The root of the equation |(x,alpha,1),(b...

The root of the equation `|(x,alpha,1),(beta,x,1),(beta,gamma,1)| = 0` are independent of :

A

(a) `alpha`

B

(b) `beta`

C

(c) `gamma`

D

(d) `alpha, beta and gamma`

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To solve the determinant equation \(|(x, \alpha, 1), (\beta, x, 1), (\beta, \gamma, 1)| = 0\) and determine which variable the roots are independent of, we can follow these steps: ### Step 1: Write the Determinant We start with the determinant: \[ D = \begin{vmatrix} x & \alpha & 1 \\ \beta & x & 1 \\ \beta & \gamma & 1 \end{vmatrix} \] ### Step 2: Expand the Determinant Using the first row to expand the determinant: \[ D = x \begin{vmatrix} x & 1 \\ \gamma & 1 \end{vmatrix} - \alpha \begin{vmatrix} \beta & 1 \\ \beta & 1 \end{vmatrix} + 1 \begin{vmatrix} \beta & x \\ \beta & \gamma \end{vmatrix} \] ### Step 3: Calculate the 2x2 Determinants Now we calculate each of the 2x2 determinants: 1. For the first determinant: \[ \begin{vmatrix} x & 1 \\ \gamma & 1 \end{vmatrix} = x \cdot 1 - \gamma \cdot 1 = x - \gamma \] 2. For the second determinant: \[ \begin{vmatrix} \beta & 1 \\ \beta & 1 \end{vmatrix} = \beta \cdot 1 - \beta \cdot 1 = 0 \] 3. For the third determinant: \[ \begin{vmatrix} \beta & x \\ \beta & \gamma \end{vmatrix} = \beta \cdot \gamma - \beta \cdot x = \beta(\gamma - x) \] ### Step 4: Substitute Back into the Determinant Substituting these results back into the determinant: \[ D = x(x - \gamma) - \alpha \cdot 0 + \beta(\gamma - x) \] This simplifies to: \[ D = x^2 - x\gamma + \beta\gamma - \beta x \] Rearranging gives: \[ D = x^2 - (\gamma + \beta)x + \beta\gamma \] ### Step 5: Set the Determinant to Zero For the determinant to be zero: \[ x^2 - (\gamma + \beta)x + \beta\gamma = 0 \] ### Step 6: Analyze the Roots The roots of the quadratic equation are given by: \[ x = \frac{(\gamma + \beta) \pm \sqrt{(\gamma + \beta)^2 - 4\beta\gamma}}{2} \] The roots depend on the coefficients \(\gamma\) and \(\beta\), but do not depend on \(\alpha\). ### Conclusion Thus, the roots of the equation are independent of \(\alpha\).
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