

InterviewSolution
Saved Bookmarks
1. |
If \(x^2+\frac{1}{x^2}\) = 18, find the values of \(x+\frac{1}{x}\) and \(x-\frac{1}{x}\). |
Answer» x2 + \(\frac{1}{x\times x}\) = 18 Adding 2 on both sides, we get x2 + \(\frac{1}{x\times x}\) + 2 = 18 + 2 x2 + \(\frac{1}{x\times x}\) + 2 × x × \(\frac{1}{x}\) = 20 (x + \(\frac{1}{x}\) )2 = 20 x + \(\frac{1}{x}\) = \(2\sqrt{5}\) Given that, x2 + \(\frac{1}{x\times x}\) = 18 Subtracting 2 from both sides, we get x2 +\(\frac{1}{x\times x}\) - 2 × x × \(\frac{1}{x}\) = 18 – 2 (x - \(\frac{1}{x}\))2 = 16 x - \(\frac{1}{x}\) = 4 |
|