Question

If $7=x^2+\frac{1}{x^2}$, then what is the greatest possible value of $x+\frac{1}{x}$?

Answer 1

3

Explanation:

7 = x² + 1/(x²)

7 + 2 = x² + 2 + 1/(x²)

9 = (x + 1/x)²

±3 = x + 1/x