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Given the `alpha + beta` are the roots of the quadratic equation `px^(2) + qx + 1 = 0` find the value of `alpha^(3)beta^(2) + alpha^(2)beta^(3)`.

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To solve the problem, we need to find the value of \( \alpha^3 \beta^2 + \alpha^2 \beta^3 \) given that \( \alpha \) and \( \beta \) are the roots of the quadratic equation \( px^2 + qx + 1 = 0 \). ### Step-by-Step Solution: 1. **Identify the coefficients**: The given quadratic equation is \( px^2 + qx + 1 = 0 \). Here, we identify: - \( a = p \) - \( b = q \) - \( c = 1 \) 2. **Use Vieta's Formulas**: According to Vieta's formulas: - The sum of the roots \( \alpha + \beta = -\frac{b}{a} = -\frac{q}{p} \) - The product of the roots \( \alpha \beta = \frac{c}{a} = \frac{1}{p} \) 3. **Rewrite the expression**: We need to find \( \alpha^3 \beta^2 + \alpha^2 \beta^3 \). This can be factored as: \[ \alpha^3 \beta^2 + \alpha^2 \beta^3 = \alpha^2 \beta^2 (\alpha + \beta) \] 4. **Substitute the values**: We already found: - \( \alpha + \beta = -\frac{q}{p} \) - \( \alpha \beta = \frac{1}{p} \) Therefore, \( \alpha^2 \beta^2 = (\alpha \beta)^2 = \left(\frac{1}{p}\right)^2 = \frac{1}{p^2} \). 5. **Combine the results**: Now substitute these values into the expression: \[ \alpha^3 \beta^2 + \alpha^2 \beta^3 = \alpha^2 \beta^2 (\alpha + \beta) = \frac{1}{p^2} \left(-\frac{q}{p}\right) \] Simplifying this gives: \[ = -\frac{q}{p^3} \] ### Final Answer: Thus, the value of \( \alpha^3 \beta^2 + \alpha^2 \beta^3 \) is: \[ -\frac{q}{p^3} \]
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