JEE Mains · Maths · STD 11 - 4.2 Quadratic equations and inequations
The number of real solutions of the equation \(3\left(x^2+\frac{1}{x^2}\right)-2\left(x+\frac{1}{x}\right)+5=0\), is
- A \(4\)
- B \(0\)
- C \(3\)
- D \(2\)
Answer & Solution
Correct Answer
(B) \(0\)
Step-by-step Solution
Detailed explanation
\(3\left(x^2+\frac{1}{x^2}\right)-2\left(x+\frac{1}{x}\right)+5=0\) \(3\left[\left(x+\frac{1}{x}\right)^2-2\right]-2\left(x+\frac{1}{x}\right)+5=0\) Let \(x +\frac{1}{ x }= t\) \(3 t ^2-2 t -1=0\) \(3 t ^2-3 t + t -1=0\) \(3 t ( t -1)+1( t -1)=0\) \(( t -1)(3 t +1)=0\)…
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