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If alpha,beta and gamma are roots of equ...

If `alpha,beta and gamma` are roots of equation `x^(3)-3x^(2)+1=0`, then the value of `((alpha)/(1+alpha))^(3)+((beta)/(1+beta))^(3)+((gamma)/(1+gamma))^(3)` is __________.

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To solve the problem, we need to find the value of \[ \left(\frac{\alpha}{1+\alpha}\right)^3 + \left(\frac{\beta}{1+\beta}\right)^3 + \left(\frac{\gamma}{1+\gamma}\right)^3 \] where \(\alpha\), \(\beta\), and \(\gamma\) are the roots of the polynomial equation \[ x^3 - 3x^2 + 1 = 0. \] ### Step 1: Identify the roots of the polynomial The roots of the polynomial \(x^3 - 3x^2 + 1 = 0\) are denoted as \(\alpha\), \(\beta\), and \(\gamma\). We can use Vieta's formulas to find the sums and products of the roots: - \(\alpha + \beta + \gamma = 3\) - \(\alpha\beta + \beta\gamma + \gamma\alpha = 0\) - \(\alpha\beta\gamma = -1\) ### Step 2: Define new variables for the roots Let: \[ \alpha_1 = \frac{\alpha}{1+\alpha}, \quad \beta_1 = \frac{\beta}{1+\beta}, \quad \gamma_1 = \frac{\gamma}{1+\gamma} \] We need to find \(\alpha_1^3 + \beta_1^3 + \gamma_1^3\). ### Step 3: Find the polynomial whose roots are \(\alpha_1\), \(\beta_1\), and \(\gamma_1\) To find the polynomial whose roots are \(\alpha_1\), \(\beta_1\), and \(\gamma_1\), we can perform a substitution in the original polynomial. We replace \(x\) with \(\frac{y}{1-y}\) (where \(y = \alpha_1\)). ### Step 4: Substitute and simplify Substituting \(x = \frac{y}{1-y}\) into the polynomial: \[ \left(\frac{y}{1-y}\right)^3 - 3\left(\frac{y}{1-y}\right)^2 + 1 = 0 \] This leads to: \[ \frac{y^3}{(1-y)^3} - 3\frac{y^2}{(1-y)^2} + 1 = 0 \] Multiplying through by \((1-y)^3\) to eliminate the denominator gives: \[ y^3 - 3y^2(1-y) + (1-y)^3 = 0 \] ### Step 5: Expand and combine like terms Expanding the equation: \[ y^3 - 3y^2 + 3y^3 - 1 + 3y^2 - 3y = 0 \] This simplifies to: \[ 3y^3 - 3y + 1 = 0 \] ### Step 6: Find the sums of roots From the polynomial \(3y^3 - 3y + 1 = 0\), we can use Vieta's formulas again: - The sum of the roots \(\alpha_1 + \beta_1 + \gamma_1 = 0\) - The sum of the products of the roots taken two at a time \(\alpha_1\beta_1 + \beta_1\gamma_1 + \gamma_1\alpha_1 = -1\) - The product of the roots \(\alpha_1\beta_1\gamma_1 = -\frac{1}{3}\) ### Step 7: Use the identity for cubes Using the identity: \[ \alpha_1^3 + \beta_1^3 + \gamma_1^3 - 3\alpha_1\beta_1\gamma_1 = (\alpha_1 + \beta_1 + \gamma_1)\left(\alpha_1^2 + \beta_1^2 + \gamma_1^2 - \alpha_1\beta_1 - \beta_1\gamma_1 - \gamma_1\alpha_1\right) \] Since \(\alpha_1 + \beta_1 + \gamma_1 = 0\), we have: \[ \alpha_1^3 + \beta_1^3 + \gamma_1^3 = 3\alpha_1\beta_1\gamma_1 \] Substituting the value of \(\alpha_1\beta_1\gamma_1 = -\frac{1}{3}\): \[ \alpha_1^3 + \beta_1^3 + \gamma_1^3 = 3 \left(-\frac{1}{3}\right) = -1 \] ### Final Answer Thus, the value of \[ \left(\frac{\alpha}{1+\alpha}\right)^3 + \left(\frac{\beta}{1+\beta}\right)^3 + \left(\frac{\gamma}{1+\gamma}\right)^3 = -1. \]

To solve the problem, we need to find the value of \[ \left(\frac{\alpha}{1+\alpha}\right)^3 + \left(\frac{\beta}{1+\beta}\right)^3 + \left(\frac{\gamma}{1+\gamma}\right)^3 \] where \(\alpha\), \(\beta\), and \(\gamma\) are the roots of the polynomial equation ...
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