I've been working on this so long, but I can't get it.
If x^2 + 1/x^2 = 3 and x > 0, what is the value of x - 1/x? Express your answer in simplest radical form.
\((x - {1\over x})^2 = x^2 - 2 + {1\over x^2} = 3 - 2 = 1\)
\(x - {1\over x} = \pm1\)