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If 0 lt a lt b lt c and equation ax^(2)+...

If `0 lt a lt b lt c` and equation `ax^(2)+bx+c=0` does not posses distinct roots (say `alpha` and `beta`), then

A

`|alpha|=|beta|`

B

`|alpha|gt1`

C

`|beta|lt 1`

D

none of these

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The correct Answer is:
To solve the problem, we start by analyzing the given quadratic equation and the conditions provided. ### Step 1: Understanding the Conditions We have the quadratic equation: \[ ax^2 + bx + c = 0 \] with the conditions: \[ 0 < a < b < c \] This means that \( a, b, c \) are all positive and \( c \) is the largest, followed by \( b \), and \( a \) is the smallest. ### Step 2: Roots of the Quadratic Equation The roots of the quadratic equation can be found using the quadratic formula: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] ### Step 3: Condition for Non-distinct Roots The equation does not possess distinct roots, which means the discriminant must be zero: \[ b^2 - 4ac = 0 \] This implies that the roots are equal, denoted as \( \alpha = \beta \). ### Step 4: Finding the Roots Since the roots are equal, we can express them as: \[ \alpha = \beta = \frac{-b}{2a} \] This shows that both roots are the same. ### Step 5: Analyzing the Roots Given that \( a, b, c > 0 \) and \( b > a \), we can analyze the value of \( \alpha \): - Since \( b \) is positive and \( a \) is positive, the expression \( -b/(2a) \) will be negative. - Therefore, both roots \( \alpha \) and \( \beta \) are negative. ### Step 6: Modulus of the Roots Since both roots are negative, we can find their modulus: \[ |\alpha| = |\beta| = -\frac{-b}{2a} = \frac{b}{2a} \] Since \( b > a \), it follows that: \[ \frac{b}{2a} > 1 \] Thus, we conclude: \[ |\alpha| > 1 \quad \text{and} \quad |\beta| > 1 \] ### Conclusion Based on the analysis, we can summarize that: - The roots \( \alpha \) and \( \beta \) are equal and negative. - Their moduli are greater than 1.
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