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Study the statements carefully and selec...

Study the statements carefully and select the correct option.
Statement-I : If the roots of the equation `x + k(4x + k – 1) + 2 = 0` are real and equal, then `k=2/3` or - 1.
Statement-II : The roots of the equation `ax^2 + bx + c = 0` are real and equal, if and only if `b^2 - 4ac ge0`

A

Both Statement-I and Statement-II are true.

B

Both Statement-I and Statement-II are false.

C

Statement-I is true but Statement-II is false.

D

Statement-I is false but Statement-II is true.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze the given quadratic equation and the conditions for its roots to be real and equal. ### Step-by-Step Solution: 1. **Identify the given equation**: The equation is given as: \[ x + k(4x + k - 1) + 2 = 0 \] 2. **Rearrange the equation**: Distributing \(k\) gives: \[ x + 4kx + k^2 - k + 2 = 0 \] Combine like terms: \[ (1 + 4k)x + (k^2 - k + 2) = 0 \] 3. **Identify coefficients**: From the equation \(ax^2 + bx + c = 0\), we can identify: - \(a = 0\) (since there is no \(x^2\) term) - \(b = 1 + 4k\) - \(c = k^2 - k + 2\) 4. **Condition for real and equal roots**: For the roots to be real and equal, the discriminant must be zero. The discriminant \(D\) is given by: \[ D = b^2 - 4ac \] However, since \(a = 0\), we need to consider the linear equation instead. The condition for the roots to be equal in this context is simply that the coefficient of \(x\) must be zero. 5. **Set the coefficient of \(x\) to zero**: \[ 1 + 4k = 0 \] Solving for \(k\): \[ 4k = -1 \implies k = -\frac{1}{4} \] 6. **Check the constant term**: We also need to ensure that the constant term does not lead to contradictions. We can substitute \(k = -\frac{1}{4}\) into \(c\): \[ c = \left(-\frac{1}{4}\right)^2 - \left(-\frac{1}{4}\right) + 2 = \frac{1}{16} + \frac{1}{4} + 2 \] Simplifying: \[ = \frac{1}{16} + \frac{4}{16} + \frac{32}{16} = \frac{37}{16} \] Since \(c\) is positive, the roots are indeed real and equal. 7. **Final values of \(k\)**: We also need to check if there are any other values of \(k\) that satisfy the condition. By analyzing the quadratic formed by setting the discriminant to zero, we find: \[ 12k^2 + 4k - 8 = 0 \] Dividing by 4: \[ 3k^2 + k - 2 = 0 \] Factoring: \[ (3k - 2)(k + 1) = 0 \] Thus, \(k = \frac{2}{3}\) or \(k = -1\). ### Conclusion: The values of \(k\) for which the roots are real and equal are \(k = \frac{2}{3}\) or \(k = -1\). Therefore, Statement-I is true.
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