JEE Mains · Maths · STD 11 - 4.2 Quadratic equations and inequations
The number of real solutions of the equation \(\mathrm{x}|\mathrm{x}+5|+2|\mathrm{x}+7|-2=0\) is ...........
- A \(9\)
- B \(3\)
- C \(6\)
- D \(1\)
Answer & Solution
Correct Answer
(B) \(3\)
Step-by-step Solution
Detailed explanation
Case \(I\) : \(x \geq-5\) \( x^2+5 x+2 x+12=0 \) \( x^2+7 x+12=0 \) \( x=-3,-4\) Case \(II\) : \(-7<\mathrm{x}<-5\) \(-x^2-5 x+2 x+14-2=0\) \( -x^2-3 x+12=0 \) \( x=\frac{-3 \pm \sqrt{9+48}}{2} \) \( =\frac{-3 \pm \sqrt{57}}{2} \)…
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