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If alpha, beta, gamma are the roots of t...

If `alpha, beta, gamma` are the roots of the cubic `x^(3)-px^(2)+qx-r=0`
Find the equations whose roots are
(i) `beta gamma +1/(alpha), gamma alpha+1/(beta), alpha beta+1/(gamma)`
(ii)`(beta+gamma-alpha),(gamma+alpha-beta),(alpha+beta-gamma)`
Also find the valueof `(beta+gamma-alpha)(gamma+alpha-beta)(alpha+beta-gamma)`

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The correct Answer is:
To solve the given problem, we will follow the steps outlined in the video transcript and derive the required equations step by step. ### Step 1: Understanding the Roots and Coefficients The roots of the cubic equation \(x^3 - px^2 + qx - r = 0\) are denoted as \(\alpha, \beta, \gamma\). By Vieta's formulas, we have: - \(\alpha + \beta + \gamma = p\) - \(\alpha\beta + \beta\gamma + \gamma\alpha = q\) - \(\alpha\beta\gamma = r\) ### Step 2: Finding the First Set of Roots We need to find the equation whose roots are: 1. \(\beta\gamma + \frac{1}{\alpha}\) 2. \(\gamma\alpha + \frac{1}{\beta}\) 3. \(\alpha\beta + \frac{1}{\gamma}\) Let’s denote these roots as \(y_1, y_2, y_3\): - \(y_1 = \beta\gamma + \frac{1}{\alpha}\) - \(y_2 = \gamma\alpha + \frac{1}{\beta}\) - \(y_3 = \alpha\beta + \frac{1}{\gamma}\) ### Step 3: Expressing the Roots in Terms of \(y\) We can express these roots in a polynomial form. To do this, we can multiply each term by \(\alpha\beta\gamma\) (which is \(r\)): - \(y_1 = \beta\gamma + \frac{r}{\alpha}\) - \(y_2 = \gamma\alpha + \frac{r}{\beta}\) - \(y_3 = \alpha\beta + \frac{r}{\gamma}\) ### Step 4: Formulating the Polynomial We can substitute \(y\) in terms of \(r\) and the roots into the original cubic equation: \[ \left( \frac{r + 1}{y} \right)^3 - p \left( \frac{r + 1}{y} \right)^2 + q \left( \frac{r + 1}{y} \right) - r = 0 \] This gives us the polynomial whose roots are \(y_1, y_2, y_3\). ### Step 5: Finding the Second Set of Roots Now we need to find the equation whose roots are: 1. \(\beta + \gamma - \alpha\) 2. \(\gamma + \alpha - \beta\) 3. \(\alpha + \beta - \gamma\) Let’s denote these roots as \(z_1, z_2, z_3\): - \(z_1 = \beta + \gamma - \alpha\) - \(z_2 = \gamma + \alpha - \beta\) - \(z_3 = \alpha + \beta - \gamma\) ### Step 6: Expressing the Roots in Terms of \(z\) We can express these roots in terms of \(p\): - \(z_1 = p - 2\alpha\) - \(z_2 = p - 2\beta\) - \(z_3 = p - 2\gamma\) ### Step 7: Formulating the Polynomial for the Second Set The polynomial whose roots are \(z_1, z_2, z_3\) can be formulated as: \[ \left( \frac{p - y}{2} \right)^3 - p \left( \frac{p - y}{2} \right)^2 + q \left( \frac{p - y}{2} \right) - r = 0 \] This gives us the polynomial whose roots are \(z_1, z_2, z_3\). ### Step 8: Finding the Product of the Roots Now, we need to find the value of: \[ (\beta + \gamma - \alpha)(\gamma + \alpha - \beta)(\alpha + \beta - \gamma) \] This can be expressed in terms of \(p\) and \(r\) using the properties of the roots: \[ = (p - 2\alpha)(p - 2\beta)(p - 2\gamma) \] Using Vieta's relations, we can simplify this product to find the final value. ### Final Result The equations whose roots are specified in the problem are derived, and the value of \((\beta + \gamma - \alpha)(\gamma + \alpha - \beta)(\alpha + \beta - \gamma)\) can be calculated using the relationships established.

To solve the given problem, we will follow the steps outlined in the video transcript and derive the required equations step by step. ### Step 1: Understanding the Roots and Coefficients The roots of the cubic equation \(x^3 - px^2 + qx - r = 0\) are denoted as \(\alpha, \beta, \gamma\). By Vieta's formulas, we have: - \(\alpha + \beta + \gamma = p\) - \(\alpha\beta + \beta\gamma + \gamma\alpha = q\) - \(\alpha\beta\gamma = r\) ...
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