If (x + 1/x) = 5√2, then what is the value of (x4 + x-4)?

If $(x + \frac{1}{x}) = 5\sqrt{2}$

what is the value of (x⁴ + x^-4)

$(x + \frac{1}{x}) = 5\sqrt{2}$

(x² + x^-2) = (5\(\sqrt {2}\))² - 2 = 48

= (x⁴ + x^-4) = 48² - 2 = 2302