>>924

1/X = √3 + √2,
X = √3 - √2,
より
1/X + X = 2√3,
1/X - X = 2√2,
辺々掛けて
1/XX - XX = 4√6,

1/X^4 + X^4 =(1/XX - XX)^2 + 2
=(4√6)^2 + 2
= 98,