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ax^2 + bx + c = 0(a > 0), has two roots ...

`ax^2 + bx + c = 0(a > 0),` has two roots `alpha and beta` such `alpha < -2 and beta > 2,` then

A

` a - |b| + c lt 0 `

B

` c lt 0, b^(2) - 4ac gt 0 `

C

`4a - 2 |b| + c lt 0 `

D

` 9a - 3 |b| + c lt 0 `

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To solve the equation \( ax^2 + bx + c = 0 \) with the conditions given, we will analyze the roots \( \alpha \) and \( \beta \) based on the properties of quadratic equations. ### Step 1: Understanding the Quadratic Equation The quadratic equation is given by: \[ f(x) = ax^2 + bx + c \] where \( a > 0 \). This means the parabola opens upwards. ### Step 2: Analyzing the Roots We know that: - \( \alpha < -2 \) - \( \beta > 2 \) This indicates that the graph of the quadratic function must cross the x-axis at two points, one to the left of -2 and one to the right of 2. ### Step 3: Determining the Nature of Roots For the quadratic equation to have two distinct real roots, the discriminant must be greater than zero: \[ D = b^2 - 4ac > 0 \] ### Step 4: Evaluating the Value of \( c \) Since the parabola opens upwards and has roots \( \alpha \) and \( \beta \), the vertex of the parabola must be located between the two roots. The vertex \( x_v \) is given by: \[ x_v = -\frac{b}{2a} \] Since \( \alpha < -2 \) and \( \beta > 2 \), it follows that \( -2 < x_v < 2 \). ### Step 5: Finding \( f(0) \) The value of \( f(0) \) gives us the y-intercept, which is \( c \): \[ f(0) = c \] Since the graph is below the x-axis between the roots, we know that \( c < 0 \). ### Step 6: Analyzing the Conditions for \( a, b, c \) We need to check the conditions for \( a + b + c < 0 \) and \( a - 2b + c < 0 \): 1. **Condition 1**: \( a + b + c < 0 \) 2. **Condition 2**: \( a - 2b + c < 0 \) ### Step 7: Conclusion From the analysis, we can conclude that: - The discriminant \( b^2 - 4ac > 0 \) ensures two distinct roots. - The y-intercept \( c < 0 \) ensures the graph is below the x-axis at \( x = 0 \). - The conditions involving \( a, b, c \) must be checked to determine which options are valid. ### Final Answer Based on the analysis, the correct options can be determined from the conditions derived above.

To solve the equation \( ax^2 + bx + c = 0 \) with the conditions given, we will analyze the roots \( \alpha \) and \( \beta \) based on the properties of quadratic equations. ### Step 1: Understanding the Quadratic Equation The quadratic equation is given by: \[ f(x) = ax^2 + bx + c \] where \( a > 0 \). This means the parabola opens upwards. ...
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