4・32 Try to solve the equation $x^{4}+(x-4)^{4}=626$.


[Solution] Let the substitution $y=x-2$, then the original equation becomes
$$
(y+2)^{4}+(y-2)^{4}=626 \text {, }
$$

which simplifies to $y^{4}+24 y^{2}-297=0$.
Thus, $y^{2}=9,-33$; i.e., $y= \pm 3, \pm \sqrt{33} i$,
so the two real roots and two complex roots of the original equation are:
$$
5,-1 ; 2+\sqrt{33} i, 2-\sqrt{33} i \text {. }
$$