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If `alpha` and `beta` are the roots of the equation `3x^(2)+8x+2=0` then `((1)/(alpha)+(1)/(beta))=?`

A

`(-3)/(8)`

B

`(2)/(3)`

C

-4

D

4

Text Solution

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The correct Answer is:
To solve the problem, we need to find the value of \(\frac{1}{\alpha} + \frac{1}{\beta}\) where \(\alpha\) and \(\beta\) are the roots of the quadratic equation \(3x^2 + 8x + 2 = 0\). ### Step-by-Step Solution: 1. **Identify the coefficients**: The given quadratic equation is \(3x^2 + 8x + 2 = 0\). Here, we can identify: - \(A = 3\) - \(B = 8\) - \(C = 2\) 2. **Use Vieta's Formulas**: According to Vieta's formulas: - The sum of the roots \(\alpha + \beta = -\frac{B}{A}\) - The product of the roots \(\alpha \beta = \frac{C}{A}\) Substituting the values: - \(\alpha + \beta = -\frac{8}{3}\) - \(\alpha \beta = \frac{2}{3}\) 3. **Find \(\frac{1}{\alpha} + \frac{1}{\beta}\)**: We can express \(\frac{1}{\alpha} + \frac{1}{\beta}\) as follows: \[ \frac{1}{\alpha} + \frac{1}{\beta} = \frac{\beta + \alpha}{\alpha \beta} \] Substituting the values from Vieta's formulas: \[ \frac{1}{\alpha} + \frac{1}{\beta} = \frac{\alpha + \beta}{\alpha \beta} = \frac{-\frac{8}{3}}{\frac{2}{3}} \] 4. **Simplify the expression**: To simplify \(\frac{-\frac{8}{3}}{\frac{2}{3}}\): \[ = -\frac{8}{3} \times \frac{3}{2} = -\frac{8 \times 3}{3 \times 2} = -\frac{8}{2} = -4 \] 5. **Final Answer**: Therefore, the value of \(\frac{1}{\alpha} + \frac{1}{\beta}\) is \(-4\). ### Final Result: \[ \frac{1}{\alpha} + \frac{1}{\beta} = -4 \]

To solve the problem, we need to find the value of \(\frac{1}{\alpha} + \frac{1}{\beta}\) where \(\alpha\) and \(\beta\) are the roots of the quadratic equation \(3x^2 + 8x + 2 = 0\). ### Step-by-Step Solution: 1. **Identify the coefficients**: The given quadratic equation is \(3x^2 + 8x + 2 = 0\). Here, we can identify: - \(A = 3\) - \(B = 8\) ...
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