JEE Mains · Maths · STD 11 - 4.2 Quadratic equations and inequations
The set of all \(a \in R\) for which the equation \(x | x -1|+| x +2|+a=0\) has exactly one real root is:
- A \((-6,-3)\)
- B \((-\infty, \infty)\)
- C \((-6, \infty)\)
- D \((-\infty,-3)\)
Answer & Solution
Correct Answer
(B) \((-\infty, \infty)\)
Step-by-step Solution
Detailed explanation
\(f(x)=x|x-1|+|x+2|\) \(x|x-1|+|x+2|+a=0\) \(x|x-1|+|x+2|=-a\) All values are increasing.
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