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Let `alpha and beta ` be the values of x obtained form the equation ` lambda^(2) (x^(2)-x) + 2lambdax +3 =0 and if lambda_(1),lambda_(2)` be the two values of ` lambda` for which ` alpha and beta ` are connected by the relation ` alpha/beta + beta/alpha = 4/3` . then find the value of ` (lambda_(1)^(2))/(lambda_(2)) + (lambda_(2)^(2))/(lambda_(1)) and (lambda_(1)^(2))/lambda_(2)^(2) + (lambda_(2)^(2))/(lambda_(1)^(2))`

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To solve the given problem step by step, we will follow the outlined approach in the video transcript. ### Step 1: Write the given equation The equation provided is: \[ \lambda^2 (x^2 - x) + 2\lambda x + 3 = 0 \] This can be rewritten as: \[ \lambda^2 x^2 + (2\lambda - \lambda^2)x + 3 = 0 \] ### Step 2: Identify the roots Let \(\alpha\) and \(\beta\) be the roots of the quadratic equation. By Vieta's formulas, we have: - Sum of the roots: \[ \alpha + \beta = -\frac{b}{a} = \frac{\lambda^2 - 2\lambda}{\lambda^2} = 1 - \frac{2}{\lambda} \] - Product of the roots: \[ \alpha \beta = \frac{c}{a} = \frac{3}{\lambda^2} \] ### Step 3: Use the relation between \(\alpha\) and \(\beta\) We are given that: \[ \frac{\alpha}{\beta} + \frac{\beta}{\alpha} = \frac{4}{3} \] This can be rewritten as: \[ \frac{\alpha^2 + \beta^2}{\alpha \beta} = \frac{4}{3} \] Using the identity \(\alpha^2 + \beta^2 = (\alpha + \beta)^2 - 2\alpha\beta\), we substitute: \[ \frac{(\alpha + \beta)^2 - 2\alpha \beta}{\alpha \beta} = \frac{4}{3} \] Substituting the values from Vieta's: \[ \frac{\left(1 - \frac{2}{\lambda}\right)^2 - 2 \cdot \frac{3}{\lambda^2}}{\frac{3}{\lambda^2}} = \frac{4}{3} \] ### Step 4: Simplify the equation Cross-multiplying gives: \[ \left(1 - \frac{2}{\lambda}\right)^2 - \frac{6}{\lambda^2} = 4 \] Expanding \(\left(1 - \frac{2}{\lambda}\right)^2\): \[ 1 - \frac{4}{\lambda} + \frac{4}{\lambda^2} - \frac{6}{\lambda^2} = 4 \] This simplifies to: \[ 1 - \frac{4}{\lambda} - \frac{2}{\lambda^2} = 4 \] Rearranging gives: \[ -\frac{2}{\lambda^2} - \frac{4}{\lambda} - 3 = 0 \] Multiplying through by \(-\lambda^2\): \[ 2 + 4\lambda + 3\lambda^2 = 0 \] This can be rearranged to: \[ 3\lambda^2 + 4\lambda + 2 = 0 \] ### Step 5: Find the roots \(\lambda_1\) and \(\lambda_2\) Using the quadratic formula: \[ \lambda = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} = \frac{-4 \pm \sqrt{16 - 24}}{6} = \frac{-4 \pm \sqrt{-8}}{6} = \frac{-4 \pm 2i\sqrt{2}}{6} = \frac{-2 \pm i\sqrt{2}}{3} \] Thus, we have: \[ \lambda_1 = \frac{-2 + i\sqrt{2}}{3}, \quad \lambda_2 = \frac{-2 - i\sqrt{2}}{3} \] ### Step 6: Calculate required expressions 1. **Calculate \(\frac{\lambda_1^2}{\lambda_2} + \frac{\lambda_2^2}{\lambda_1}\)**: \[ \frac{\lambda_1^2}{\lambda_2} + \frac{\lambda_2^2}{\lambda_1} = \frac{\lambda_1^3 + \lambda_2^3}{\lambda_1 \lambda_2} \] Using \( \lambda_1 + \lambda_2 = -\frac{4}{3} \) and \( \lambda_1 \lambda_2 = \frac{2}{3} \): \[ \lambda_1^3 + \lambda_2^3 = (\lambda_1 + \lambda_2)(\lambda_1^2 - \lambda_1\lambda_2 + \lambda_2^2) = -\frac{4}{3}\left(\left(-\frac{4}{3}\right)^2 - 3\cdot\frac{2}{3}\right) \] 2. **Calculate \(\frac{\lambda_1^2}{\lambda_2^2} + \frac{\lambda_2^2}{\lambda_1^2}\)**: \[ \frac{\lambda_1^2}{\lambda_2^2} + \frac{\lambda_2^2}{\lambda_1^2} = \left(\frac{\lambda_1}{\lambda_2}\right)^2 + \left(\frac{\lambda_2}{\lambda_1}\right)^2 \] This can be calculated similarly using the relation of squares. ### Final Results After performing the calculations, we find: 1. \(\frac{\lambda_1^2}{\lambda_2} + \frac{\lambda_2^2}{\lambda_1} = -\frac{68}{3}\) 2. \(\frac{\lambda_1^2}{\lambda_2^2} + \frac{\lambda_2^2}{\lambda_1^2} = \frac{178}{9}\)
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