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Let p and q be real numbers such that `p ne 0, p^(3) ne q and p^(3) ne -q.` If `alpha and beta` are non-zero complex number satisfying `alpha +beta=-p and alpha^(3)+beta^(3)=q`, then a quadratic equation having `(alpha)/(beta) ,(beta)/(alpha)` as its root is

A

`(p^(3)+q)x^(2)-(p^(3)+2q)x+(p^(3)+q)=0`

B

`(p^(3)+q)x^(2)-(p^(3)-2q)x+(p^(3)+q)=0`

C

`(p^(3)-q) x^(2)-(5p^(3)-2q)x+(p^(3)-q)=0`

D

`(p^(3)-q)x^(2)-(5p^(3)+2q)x+(p^(3)-q)=0`

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To solve the problem, we need to find a quadratic equation with roots \(\frac{\alpha}{\beta}\) and \(\frac{\beta}{\alpha}\). We will follow these steps: ### Step 1: Identify the Roots The roots of the quadratic equation we want to form are: \[ r_1 = \frac{\alpha}{\beta}, \quad r_2 = \frac{\beta}{\alpha} \] ### Step 2: Calculate the Sum of Roots The sum of the roots \(r_1 + r_2\) can be calculated as follows: \[ r_1 + r_2 = \frac{\alpha}{\beta} + \frac{\beta}{\alpha} = \frac{\alpha^2 + \beta^2}{\alpha \beta} \] ### Step 3: Calculate the Product of Roots The product of the roots \(r_1 \cdot r_2\) is: \[ r_1 \cdot r_2 = \frac{\alpha}{\beta} \cdot \frac{\beta}{\alpha} = 1 \] ### Step 4: Form the Quadratic Equation Using the standard form of a quadratic equation \(x^2 - (r_1 + r_2)x + (r_1 \cdot r_2) = 0\), we substitute the values we found: \[ x^2 - \left(\frac{\alpha^2 + \beta^2}{\alpha \beta}\right)x + 1 = 0 \] ### Step 5: Find \(\alpha^2 + \beta^2\) We know from the problem that: \[ \alpha + \beta = -p \] Squaring both sides gives: \[ (\alpha + \beta)^2 = p^2 \implies \alpha^2 + \beta^2 + 2\alpha\beta = p^2 \implies \alpha^2 + \beta^2 = p^2 - 2\alpha\beta \] ### Step 6: Substitute \(\alpha^2 + \beta^2\) into the Equation Now, we need to express \(\alpha \beta\). From the identity for \(\alpha^3 + \beta^3\): \[ \alpha^3 + \beta^3 = (\alpha + \beta)(\alpha^2 - \alpha\beta + \beta^2) = q \] Substituting \(\alpha + \beta = -p\): \[ q = -p(\alpha^2 - \alpha\beta + \beta^2) = -p((\alpha^2 + \beta^2) - \alpha\beta) \] Substituting \(\alpha^2 + \beta^2 = p^2 - 2\alpha\beta\): \[ q = -p((p^2 - 2\alpha\beta) - \alpha\beta) = -p(p^2 - 3\alpha\beta) \] Rearranging gives: \[ \alpha\beta = \frac{p^3 + q}{3p} \] ### Step 7: Substitute \(\alpha\beta\) into the Quadratic Equation Now substituting \(\alpha^2 + \beta^2\) and \(\alpha\beta\) into the quadratic equation: \[ x^2 - \left(\frac{p^2 - 2\left(\frac{p^3 + q}{3p}\right)}{\frac{p^3 + q}{3p}}\right)x + 1 = 0 \] ### Final Form of the Quadratic Equation After simplification, we multiply through by \(3p\) to eliminate the fraction: \[ 3p x^2 - (p^3 + q - 2q)x + 3p = 0 \] This simplifies to: \[ 3p x^2 - (p^3 - q)x + 3p = 0 \] ### Conclusion The quadratic equation having roots \(\frac{\alpha}{\beta}\) and \(\frac{\beta}{\alpha}\) is: \[ 3p x^2 - (p^3 - q)x + 3p = 0 \]
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