Question

(3)已知x/x2＋x＋1＝1/4,x2/x4＋x2＋1的值

Answer 1

x/(x²+x+1)=1/(x+1+1/x)=1/4

x+1+1/x=4

x+1/x=3

x²/(x^4+x²+1)

=1/(x²+1/x²+1)

=1/[(x+1/x)²-1]

=1/[3²-1]

=1/8