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If alpha, beta are the roots of the equa...

If `alpha, beta` are the roots of the equation `lambda(x^(2)-x)+x+5=0` and if `lambda_(1) and lambda_(2)` are two values of `lambda` obtained from `(alpha)/(beta)+(beta)/(alpha)=(4)/(5)`, then `(lambda_(1))/(lambda_(2)^(2))+(lambda_(2))/(lambda_(1)^(2))` equals

A

4192

B

4144

C

4096

D

4048

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The correct Answer is:
To solve the given problem, we need to follow these steps: 1. **Rewrite the equation**: The given equation is \[ \lambda(x^2 - x) + x + 5 = 0. \] We can rearrange it to: \[ \lambda x^2 + (1 - \lambda)x + 5 = 0. \] 2. **Identify coefficients**: From the standard form \(Ax^2 + Bx + C = 0\), we have: - \(A = \lambda\) - \(B = 1 - \lambda\) - \(C = 5\) 3. **Use Vieta's formulas**: The roots \(\alpha\) and \(\beta\) of the quadratic equation satisfy: - \(\alpha + \beta = -\frac{B}{A} = -\frac{1 - \lambda}{\lambda}\) - \(\alpha \beta = \frac{C}{A} = \frac{5}{\lambda}\) 4. **Set up the equation**: We are given that \[ \frac{\alpha}{\beta} + \frac{\beta}{\alpha} = \frac{4}{5}. \] This can be rewritten using the identity \(\frac{\alpha^2 + \beta^2}{\alpha \beta}\): \[ \frac{\alpha^2 + \beta^2}{\alpha \beta} = \frac{4}{5}. \] We know that \(\alpha^2 + \beta^2 = (\alpha + \beta)^2 - 2\alpha\beta\). Thus, \[ \frac{(\alpha + \beta)^2 - 2\alpha\beta}{\alpha \beta} = \frac{4}{5}. \] 5. **Substitute values**: Substitute \(\alpha + \beta\) and \(\alpha \beta\): \[ \frac{\left(-\frac{1 - \lambda}{\lambda}\right)^2 - 2 \cdot \frac{5}{\lambda}}{\frac{5}{\lambda}} = \frac{4}{5}. \] Simplifying gives: \[ \frac{\frac{(1 - \lambda)^2}{\lambda^2} - \frac{10}{\lambda}}{\frac{5}{\lambda}} = \frac{4}{5}. \] Multiplying both sides by \(\frac{5}{\lambda}\) leads to: \[ (1 - \lambda)^2 - 10 = 4. \] Therefore, \[ (1 - \lambda)^2 = 14. \] 6. **Solve for \(\lambda\)**: Taking the square root gives: \[ 1 - \lambda = \pm \sqrt{14}. \] Thus, we have two values for \(\lambda\): \[ \lambda_1 = 1 - \sqrt{14}, \quad \lambda_2 = 1 + \sqrt{14}. \] 7. **Calculate \(\frac{\lambda_1}{\lambda_2^2} + \frac{\lambda_2}{\lambda_1^2}\)**: First, compute \(\lambda_1 \lambda_2\): \[ \lambda_1 \lambda_2 = (1 - \sqrt{14})(1 + \sqrt{14}) = 1 - 14 = -13. \] Next, compute \(\lambda_1 + \lambda_2\): \[ \lambda_1 + \lambda_2 = (1 - \sqrt{14}) + (1 + \sqrt{14}) = 2. \] 8. **Use the identity**: We can use the identity: \[ \frac{\lambda_1^3 + \lambda_2^3}{\lambda_1 \lambda_2^2} = \frac{(\lambda_1 + \lambda_2)(\lambda_1^2 - \lambda_1 \lambda_2 + \lambda_2^2)}{\lambda_1 \lambda_2^2}. \] We know: \[ \lambda_1^2 + \lambda_2^2 = (\lambda_1 + \lambda_2)^2 - 2\lambda_1 \lambda_2 = 2^2 - 2(-13) = 4 + 26 = 30. \] Thus, \[ \lambda_1^3 + \lambda_2^3 = (\lambda_1 + \lambda_2)(\lambda_1^2 - \lambda_1 \lambda_2 + \lambda_2^2) = 2(30 + 13) = 2 \times 43 = 86. \] 9. **Final calculation**: \[ \frac{86}{-13} = -\frac{86}{13}. \] Thus, the final answer is: \[ \frac{\lambda_1}{\lambda_2^2} + \frac{\lambda_2}{\lambda_1^2} = -\frac{86}{13}. \]

To solve the given problem, we need to follow these steps: 1. **Rewrite the equation**: The given equation is \[ \lambda(x^2 - x) + x + 5 = 0. \] We can rearrange it to: \[ ...
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