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Let a, b, c be real, if ax^(2)+bx+c=0 ha...

Let a, b, c be real, if `ax^(2)+bx+c=0` has two real roots `alpha, beta,` where `alt-1 and betagt1`, then the value of `1+(c)/(a)+|(b)/(a)|` is :

A

a. less than -1

B

b. greater than zero

C

c. equal to zero

D

d. equal to `b^(2)-4ac`

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The correct Answer is:
To solve the problem, we need to analyze the quadratic equation \( ax^2 + bx + c = 0 \) given the conditions on its roots \( \alpha \) and \( \beta \). ### Step-by-Step Solution: 1. **Understanding the Roots**: We know that the roots \( \alpha \) and \( \beta \) satisfy \( \alpha < -1 \) and \( \beta > 1 \). This implies that the quadratic function must cross the x-axis at two points: one to the left of -1 and one to the right of 1. 2. **Evaluating the Function at Critical Points**: We evaluate the quadratic function at \( x = -1 \) and \( x = 1 \): - For \( x = -1 \): \[ f(-1) = a(-1)^2 + b(-1) + c = a - b + c \] - For \( x = 1 \): \[ f(1) = a(1)^2 + b(1) + c = a + b + c \] 3. **Applying the Conditions**: Since \( \alpha < -1 \) implies \( f(-1) > 0 \) (the function must be above the x-axis at this point): \[ a - b + c > 0 \quad \text{(1)} \] Since \( \beta > 1 \) implies \( f(1) < 0 \) (the function must be below the x-axis at this point): \[ a + b + c < 0 \quad \text{(2)} \] 4. **Rearranging the Inequalities**: From inequality (1): \[ c > -a + b \quad \text{(3)} \] From inequality (2): \[ c < -a - b \quad \text{(4)} \] 5. **Combining the Inequalities**: From (3) and (4), we can combine these inequalities: \[ -a + b < c < -a - b \] 6. **Finding \( \frac{c}{a} + \left| \frac{b}{a} \right| \)**: We want to find the value of: \[ 1 + \frac{c}{a} + \left| \frac{b}{a} \right| \] Let's denote \( \frac{c}{a} = k \), then we can express our inequalities in terms of \( k \): \[ -1 + \frac{b}{a} < k < -1 - \frac{b}{a} \] 7. **Analyzing the Expression**: If we denote \( \frac{b}{a} = m \), then we can rewrite the inequalities: \[ -1 + m < k < -1 - m \] This leads us to conclude that: \[ k + |m| < -1 \] 8. **Final Calculation**: From the inequalities, we can deduce: \[ 1 + k + |m| < 0 \] Thus, we find that: \[ 1 + \frac{c}{a} + \left| \frac{b}{a} \right| = -1 \] ### Conclusion: Therefore, the value of \( 1 + \frac{c}{a} + \left| \frac{b}{a} \right| \) is: \[ \boxed{-1} \]
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