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Let alpha and beta (a lt beta) " be the...

Let `alpha and beta (a lt beta) " be the roots of the equation " x^(2) + bx + c = 0," where " b gt 0 and c lt 0 . `
Consider the following : 1. ` beta lt -alpha` 2. `beta lt |a|`
Which of the above is//are corect ?

A

1 only

B

2 only

C

Both 1 and 2

D

Neither 1 nor 2

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The correct Answer is:
To solve the problem, we need to analyze the roots of the quadratic equation \(x^2 + bx + c = 0\) where \(b > 0\) and \(c < 0\). The roots are denoted as \(\alpha\) and \(\beta\) with the condition that \(\alpha < \beta\). ### Step 1: Find the roots of the quadratic equation The roots of the quadratic equation can be found using the quadratic formula: \[ \alpha, \beta = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] Here, \(a = 1\), \(b = b\), and \(c = c\). Thus, the roots are: \[ \alpha, \beta = \frac{-b \pm \sqrt{b^2 - 4c}}{2} \] Since \(c < 0\), the discriminant \(b^2 - 4c\) is positive, ensuring that the roots are real. ### Step 2: Determine the values of \(\alpha\) and \(\beta\) Given that \(\alpha < \beta\), we can assign: \[ \alpha = \frac{-b - \sqrt{b^2 - 4c}}{2}, \quad \beta = \frac{-b + \sqrt{b^2 - 4c}}{2} \] ### Step 3: Analyze the first statement: \(\beta < -\alpha\) To check if \(\beta < -\alpha\), we first calculate \(-\alpha\): \[ -\alpha = -\left(\frac{-b - \sqrt{b^2 - 4c}}{2}\right) = \frac{b + \sqrt{b^2 - 4c}}{2} \] Now, we need to compare \(\beta\) and \(-\alpha\): \[ \beta = \frac{-b + \sqrt{b^2 - 4c}}{2} < \frac{b + \sqrt{b^2 - 4c}}{2} \] This simplifies to: \[ -b + \sqrt{b^2 - 4c} < b + \sqrt{b^2 - 4c} \] Subtracting \(\sqrt{b^2 - 4c}\) from both sides gives: \[ -b < b \] This is true since \(b > 0\). Thus, the first statement \(\beta < -\alpha\) is **correct**. ### Step 4: Analyze the second statement: \(\beta < |\alpha|\) Next, we need to check if \(\beta < |\alpha|\): Since \(\alpha\) is negative (as \(b > 0\) and \(c < 0\)), we have: \[ |\alpha| = -\alpha = \frac{b + \sqrt{b^2 - 4c}}{2} \] Now, we compare \(\beta\) and \(|\alpha|\): \[ \beta = \frac{-b + \sqrt{b^2 - 4c}}{2} < \frac{b + \sqrt{b^2 - 4c}}{2} \] This simplifies to: \[ -b + \sqrt{b^2 - 4c} < b + \sqrt{b^2 - 4c} \] Subtracting \(\sqrt{b^2 - 4c}\) from both sides gives: \[ -b < b \] This is again true since \(b > 0\). Thus, the second statement \(\beta < |\alpha|\) is also **correct**. ### Conclusion Both statements are correct: 1. \(\beta < -\alpha\) 2. \(\beta < |\alpha|\)

To solve the problem, we need to analyze the roots of the quadratic equation \(x^2 + bx + c = 0\) where \(b > 0\) and \(c < 0\). The roots are denoted as \(\alpha\) and \(\beta\) with the condition that \(\alpha < \beta\). ### Step 1: Find the roots of the quadratic equation The roots of the quadratic equation can be found using the quadratic formula: \[ \alpha, \beta = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] Here, \(a = 1\), \(b = b\), and \(c = c\). Thus, the roots are: ...
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