Question

已知a-1/a=2,求a的2次方+1/2的2次方,a的4次方+1/a的4次方的值

Answer 1

a-1/a=2 得a=1±√2;

(a^2+1/2)^2=?

a^2+1/a^2=(a-1/a)^2+2=6;

a^4+1/a^4=