If f : [1, ∞) → [2, ∞) is given by f(= x + \(\frac{1}{x}\), then f-1 equals to
A. \(\frac{x+\sqrt{x^{2}-4}}{2}\)
B. \(\frac{x}{1+x^{2}}\)
C. \(\frac{x-\sqrt{x^{2}-4}}{2}\)
D. \(1+\sqrt{x^{2}-4}\)
Answer:A
If f : [1, ∞) → [2, ∞) is given by f(= x + \(\frac{1}{x}\), then f-1 equals to
A. \(\frac{x+\sqrt{x^{2}-4}}{2}\) B. \(\frac{x}{1+x^{2}}\) C. \(\frac{x-\sqrt{x^{2}-4}}{2}\) D. \(1+\sqrt{x^{2}-4}\)