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If 2x^(3) + 3x^(2) + 5x +6=0 has roots a...

If `2x^(3) + 3x^(2) + 5x +6=0` has roots `alpha, beta, gamma` then find `alpha + beta + gamma, alphabeta + betagamma + gammaalpha` and `alpha beta gamma`

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To solve the cubic equation \(2x^3 + 3x^2 + 5x + 6 = 0\) and find the values of \(\alpha + \beta + \gamma\), \(\alpha\beta + \beta\gamma + \gamma\alpha\), and \(\alpha\beta\gamma\), we will use Vieta's formulas. ### Step 1: Identify coefficients The general form of a cubic equation is given by: \[ ax^3 + bx^2 + cx + d = 0 \] From the given equation \(2x^3 + 3x^2 + 5x + 6 = 0\), we can identify: - \(a = 2\) - \(b = 3\) - \(c = 5\) - \(d = 6\) ### Step 2: Calculate \(\alpha + \beta + \gamma\) According to Vieta's formulas, the sum of the roots \(\alpha + \beta + \gamma\) can be calculated as: \[ \alpha + \beta + \gamma = -\frac{b}{a} \] Substituting the values of \(b\) and \(a\): \[ \alpha + \beta + \gamma = -\frac{3}{2} \] ### Step 3: Calculate \(\alpha\beta + \beta\gamma + \gamma\alpha\) The sum of the products of the roots taken two at a time is given by: \[ \alpha\beta + \beta\gamma + \gamma\alpha = \frac{c}{a} \] Substituting the values of \(c\) and \(a\): \[ \alpha\beta + \beta\gamma + \gamma\alpha = \frac{5}{2} \] ### Step 4: Calculate \(\alpha\beta\gamma\) The product of the roots is given by: \[ \alpha\beta\gamma = -\frac{d}{a} \] Substituting the values of \(d\) and \(a\): \[ \alpha\beta\gamma = -\frac{6}{2} = -3 \] ### Final Results - \(\alpha + \beta + \gamma = -\frac{3}{2}\) - \(\alpha\beta + \beta\gamma + \gamma\alpha = \frac{5}{2}\) - \(\alpha\beta\gamma = -3\)
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