If x^4 + x^-4 = 194, x > 0, then the value of x +1/x is:

If x⁴ + \(\frac{1}{x^4}\) = a

then x² + \(\frac{1}{x^2}\) = \(\sqrt {a + 2}\) = b

and x + \(\frac{1}{x}\) = \(\sqrt {b + 2}\)

If $x^4 + x^{-4} = 194$

then x² + \(\frac{1}{x^2}\) = \(\sqrt {194 + 2}\) = 14

and x + \(\frac{1}{x}\) = \(\sqrt {14 + 2}\) = 4