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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 given 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 can use Vieta's formulas. ### Step-by-Step Solution: 1. **Identify coefficients**: The given equation is in the form \( ax^3 + bx^2 + cx + d = 0 \). Here, we have: - \( a = 2 \) - \( b = 3 \) - \( c = 5 \) - \( d = 6 \) 2. **Sum of the roots** \( \alpha + \beta + \gamma \): According to Vieta's formulas, the sum of the roots of the polynomial is given by: \[ \alpha + \beta + \gamma = -\frac{b}{a} \] Substituting the values: \[ \alpha + \beta + \gamma = -\frac{3}{2} \] 3. **Sum of the products of the roots taken two at a time** \( \alpha\beta + \beta\gamma + \gamma\alpha \): This is given by: \[ \alpha\beta + \beta\gamma + \gamma\alpha = \frac{c}{a} \] Substituting the values: \[ \alpha\beta + \beta\gamma + \gamma\alpha = \frac{5}{2} \] 4. **Product of the roots** \( \alpha\beta\gamma \): This is given by: \[ \alpha\beta\gamma = -\frac{d}{a} \] Substituting the values: \[ \alpha\beta\gamma = -\frac{6}{2} = -3 \] ### Final Answers: - \( \alpha + \beta + \gamma = -\frac{3}{2} \) - \( \alpha\beta + \beta\gamma + \gamma\alpha = \frac{5}{2} \) - \( \alpha\beta\gamma = -3 \)
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