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If alpha and beta are zeroes of the quad...

If `alpha` and `beta` are zeroes of the quadratic polynomial f(x)`=3x^(2)-5x-2`, then find the value of `((alpha^(2))/(beta)+(beta^(2))/(alpha))+6(alpha+1)(beta+1)`.

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To solve the problem, we need to find the value of the expression: \[ \frac{\alpha^2}{\beta} + \frac{\beta^2}{\alpha} + 6(\alpha + 1)(\beta + 1) \] where \(\alpha\) and \(\beta\) are the roots of the quadratic polynomial \(f(x) = 3x^2 - 5x - 2\). ### Step 1: Find the sum and product of the roots For a quadratic polynomial of the form \(ax^2 + bx + c\), the sum and product of the roots can be calculated using the formulas: - Sum of roots (\(\alpha + \beta\)) = \(-\frac{b}{a}\) - Product of roots (\(\alpha \beta\)) = \(\frac{c}{a}\) Here, \(a = 3\), \(b = -5\), and \(c = -2\). Calculating the sum: \[ \alpha + \beta = -\frac{-5}{3} = \frac{5}{3} \] Calculating the product: \[ \alpha \beta = \frac{-2}{3} \] ### Step 2: Substitute the values into the expression Now we can rewrite the expression \(\frac{\alpha^2}{\beta} + \frac{\beta^2}{\alpha}\) using the sum and product of the roots. Using the identity: \[ \frac{\alpha^2}{\beta} + \frac{\beta^2}{\alpha} = \frac{\alpha^3 + \beta^3}{\alpha \beta} \] We can find \(\alpha^3 + \beta^3\) using the formula: \[ \alpha^3 + \beta^3 = (\alpha + \beta)(\alpha^2 - \alpha\beta + \beta^2) \] We know: \[ \alpha^2 + \beta^2 = (\alpha + \beta)^2 - 2\alpha\beta \] Substituting the values: \[ \alpha^2 + \beta^2 = \left(\frac{5}{3}\right)^2 - 2\left(-\frac{2}{3}\right) = \frac{25}{9} + \frac{4}{3} = \frac{25}{9} + \frac{12}{9} = \frac{37}{9} \] Now substituting back: \[ \alpha^3 + \beta^3 = \left(\frac{5}{3}\right)\left(\frac{37}{9} + \frac{2}{3}\right) \] Calculating \(\frac{2}{3}\) in terms of ninths: \[ \frac{2}{3} = \frac{6}{9} \] So, \[ \alpha^3 + \beta^3 = \left(\frac{5}{3}\right)\left(\frac{37 + 6}{9}\right) = \left(\frac{5}{3}\right)\left(\frac{43}{9}\right) = \frac{215}{27} \] Now substituting into the expression: \[ \frac{\alpha^2}{\beta} + \frac{\beta^2}{\alpha} = \frac{\frac{215}{27}}{-\frac{2}{3}} = \frac{215 \times 3}{27 \times -2} = -\frac{645}{54} \] ### Step 3: Calculate \(6(\alpha + 1)(\beta + 1)\) Now we calculate \(6(\alpha + 1)(\beta + 1)\): \[ (\alpha + 1)(\beta + 1) = \alpha \beta + \alpha + \beta + 1 = -\frac{2}{3} + \frac{5}{3} + 1 = -\frac{2}{3} + \frac{5}{3} + \frac{3}{3} = \frac{6}{3} = 2 \] Thus, \[ 6(\alpha + 1)(\beta + 1) = 6 \times 2 = 12 \] ### Step 4: Combine the results Now, we combine the results: \[ \frac{\alpha^2}{\beta} + \frac{\beta^2}{\alpha} + 6(\alpha + 1)(\beta + 1) = -\frac{645}{54} + 12 \] Converting 12 into a fraction with a denominator of 54: \[ 12 = \frac{648}{54} \] So, \[ -\frac{645}{54} + \frac{648}{54} = \frac{3}{54} = \frac{1}{18} \] ### Final Answer Thus, the value of the expression is: \[ \boxed{\frac{1}{18}} \]

To solve the problem, we need to find the value of the expression: \[ \frac{\alpha^2}{\beta} + \frac{\beta^2}{\alpha} + 6(\alpha + 1)(\beta + 1) \] where \(\alpha\) and \(\beta\) are the roots of the quadratic polynomial \(f(x) = 3x^2 - 5x - 2\). ...
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