If $x^4-62 x^2+1=0$, where $x>0$, then the value of $x^3+x^{-3}$ is:

500 512 488 364

488

If $x^4-62 x^2+1=0$, where $x>0$, then the value of $x^3+x^{-3}$  If, x2 + \(\frac{1}{x^2}\) = b then, x + \(\frac{1}{x}\) = \(\sqrt {b + 2}\) If $x^4-62 x^2+1=0$ Then, x2 + \(\frac{1}{x^2}\) = 62 and, x + \(\frac{1}{x}\) = \(\sqrt {62 + 2}\) = 8 $x^3+x^{-3}$ = 83 - 3 × 8 = 488