JEE Mains · Maths · STD 11 - 4.2 Quadratic equations and inequations
The sum of all the roots of the equation \(\left|x^2-8 x+15\right|-2 x+7=0\) is:
- A \(9+\sqrt{3}\)
- B \(11+\sqrt{3}\)
- C \(9-\sqrt{3}\)
- D \(11-\sqrt{3}\)
Answer & Solution
Correct Answer
(A) \(9+\sqrt{3}\)
Step-by-step Solution
Detailed explanation
For \(x \leq 3\) or \(x \geq 5\) \(x^2-8 x+15-2 x+7=0\) \(x=5+\sqrt{3}\) For \(3 < x < 5, x^2-8 x+15+2 x-7=0\) \(x =4\) Hence sum \(=9+\sqrt{3}\)
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