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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

`b^(2)-4acgt0`

B

`clt0`

C

`a+|b|+clt0`

D

`4a+2|b|+clt0`

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To solve the problem step by step, we will analyze the quadratic equation \( ax^2 + bx + c = 0 \) under the given conditions. ### Step 1: Understand the conditions We know that: - The roots of the equation are \( \alpha \) and \( \beta \). - \( \alpha < -2 \) and \( \beta > 2 \). - \( a > 0 \). ### Step 2: Analyze the function at specific points We will evaluate the function \( f(x) = ax^2 + bx + c \) at specific points to derive conditions on \( b \) and \( c \). ### Step 3: Evaluate \( f(0) \) Calculating \( f(0) \): \[ f(0) = c \] Since \( f(0) < 0 \) (because the parabola opens upwards and has roots on either side of the y-axis), we have: \[ c < 0 \] ### Step 4: Evaluate \( f(2) \) Next, we evaluate \( f(2) \): \[ f(2) = 4a + 2b + c \] Given that \( \beta > 2 \), it implies that the function must be negative at \( x = 2 \): \[ f(2) < 0 \implies 4a + 2b + c < 0 \] ### Step 5: Evaluate \( f(-2) \) Now, we evaluate \( f(-2) \): \[ f(-2) = 4a - 2b + c \] Since \( \alpha < -2 \), it implies that the function must also be negative at \( x = -2 \): \[ f(-2) < 0 \implies 4a - 2b + c < 0 \] ### Step 6: Derive conditions from inequalities We now have two inequalities: 1. \( 4a + 2b + c < 0 \) 2. \( 4a - 2b + c < 0 \) ### Step 7: Subtract the inequalities Subtract the second inequality from the first: \[ (4a + 2b + c) - (4a - 2b + c) < 0 \] This simplifies to: \[ 4b < 0 \implies b < 0 \] ### Step 8: Use the conditions on \( c \) Now, since \( c < 0 \) and we have \( b < 0 \), we can summarize the conditions: - \( c < 0 \) - \( b < 0 \) ### Step 9: Evaluate the discriminant For the quadratic to have real roots, the discriminant must be positive: \[ D = b^2 - 4ac > 0 \] ### Conclusion Thus, the conditions we derived are: 1. \( b < 0 \) 2. \( c < 0 \) 3. \( b^2 - 4ac > 0 \)

To solve the problem step by step, we will analyze the quadratic equation \( ax^2 + bx + c = 0 \) under the given conditions. ### Step 1: Understand the conditions We know that: - The roots of the equation are \( \alpha \) and \( \beta \). - \( \alpha < -2 \) and \( \beta > 2 \). - \( a > 0 \). ...
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