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If a gt 0 and both the roots of ax^(2) +...

If `a gt 0` and both the roots of `ax^(2) + bx + c = 0` are more than 1, then

A

`a + b + c gt 0`

B

`a + b + 4c = 0`

C

`a + b + c lt 0`

D

`a + 4b + c = 0`

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The correct Answer is:
To solve the problem, we need to analyze the conditions given in the question. We know that the quadratic equation is of the form: \[ ax^2 + bx + c = 0 \] where \( a > 0 \) and both roots (let's denote them as \( \alpha \) and \( \beta \)) are greater than 1. ### Step-by-step Solution: 1. **Understanding the Roots**: Since both roots \( \alpha \) and \( \beta \) are greater than 1, we can express this mathematically as: \[ \alpha > 1 \quad \text{and} \quad \beta > 1 \] 2. **Using Vieta's Formulas**: According to Vieta's formulas, for a quadratic equation \( ax^2 + bx + c = 0 \): - The sum of the roots \( \alpha + \beta = -\frac{b}{a} \) - The product of the roots \( \alpha \beta = \frac{c}{a} \) 3. **Analyzing the Sum of Roots**: Since both roots are greater than 1: \[ \alpha + \beta > 1 + 1 = 2 \] Therefore, we have: \[ -\frac{b}{a} > 2 \implies b < -2a \] 4. **Analyzing the Product of Roots**: Similarly, since both roots are greater than 1: \[ \alpha \beta > 1 \cdot 1 = 1 \] Thus, we have: \[ \frac{c}{a} > 1 \implies c > a \] 5. **Combining the Conditions**: From the above analysis, we have derived two conditions: - \( b < -2a \) - \( c > a \) 6. **Conclusion**: The conditions derived indicate that if \( a > 0 \) and both roots of the quadratic equation are greater than 1, then we can conclude that: - \( A + B + C > 0 \) where \( A = a \), \( B = b \), and \( C = c \). ### Final Result: Thus, the correct option based on the analysis is: \[ A + B + C > 0 \]
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