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If the equaion x^(2) + ax+ b = 0 has dis...

If the equaion `x^(2) + ax+ b = 0` has distinct real roots and `x^(2) + a|x| +b = 0` has only one real root, then

A

`b = 0 , a gt 0 `

B

b = 0, a `lt` 0

C

` b gt 0, a lt 0 `

D

`b lt 0, a gt 0 `

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To solve the problem, we need to analyze the two equations given: 1. The first equation is \( x^2 + ax + b = 0 \), which has distinct real roots. 2. The second equation is \( x^2 + a|x| + b = 0 \), which has only one real root. ### Step 1: Analyze the first equation For the equation \( x^2 + ax + b = 0 \) to have distinct real roots, the discriminant must be greater than zero. The discriminant \( D \) is given by: \[ D = a^2 - 4b \] For distinct real roots, we need: \[ D > 0 \implies a^2 - 4b > 0 \implies a^2 > 4b \quad \text{(1)} \] ### Step 2: Analyze the second equation The second equation is \( x^2 + a|x| + b = 0 \). We need to consider two cases based on the value of \( x \) (positive and negative). #### Case 1: \( x \geq 0 \) In this case, \( |x| = x \), so the equation becomes: \[ x^2 + ax + b = 0 \] This is the same as the first equation, which has distinct real roots. #### Case 2: \( x < 0 \) In this case, \( |x| = -x \), so the equation becomes: \[ x^2 - ax + b = 0 \] For this equation to have only one real root, the discriminant must be zero: \[ D = (-a)^2 - 4b = a^2 - 4b = 0 \quad \text{(2)} \] ### Step 3: Combine the results From equation (1), we have \( a^2 > 4b \). From equation (2), we have \( a^2 = 4b \). Since \( a^2 \) cannot be both greater than and equal to \( 4b \) simultaneously, we need to consider the implications of these conditions. ### Step 4: Determine the values of \( a \) and \( b \) From equation (2), we can express \( b \) in terms of \( a \): \[ b = \frac{a^2}{4} \] Substituting this into the inequality from equation (1): \[ a^2 > 4\left(\frac{a^2}{4}\right) \implies a^2 > a^2 \] This is a contradiction unless \( a^2 \) is exactly equal to \( 4b \). Therefore, we conclude that: 1. \( b = 0 \) (since if \( b \) were positive, the inequality would not hold). 2. \( a \) must be greater than 0 for the second equation to have only one root. Thus, we have: \[ b = 0 \quad \text{and} \quad a > 0 \] ### Final Result The range of values for \( a \) and \( b \) is: \[ \boxed{(a > 0, b = 0)} \]

To solve the problem, we need to analyze the two equations given: 1. The first equation is \( x^2 + ax + b = 0 \), which has distinct real roots. 2. The second equation is \( x^2 + a|x| + b = 0 \), which has only one real root. ### Step 1: Analyze the first equation For the equation \( x^2 + ax + b = 0 \) to have distinct real roots, the discriminant must be greater than zero. The discriminant \( D \) is given by: ...
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