Question

please solve it fast

Answer 1

x-1/x=7,

then
(x-1/x)²=7²,

x²+1/x² -2=49,

x²+1/x² =51

therefore
(x²+1/x²)² =(51)²,

x⁴+1/x⁴+2=(51)²,

then
x⁴+1/x⁴ =2601-2=2599

Answer 2

your answer is. 2599