m.n是方程X^2-2X-1=0 利用根与系数关系 m+n=2 mn=-1 m是方程的根 则 m^2-2m-1=0 8m=4m^2-4 3m^2-n^2-8m+1 =3m^2-n^2-4m^2+4+1 =-(m^2+n^2)+5 =-[(m+n)^2-2mn]+5 =-(4+2)+5 =-1原题有误~~,一次项系数应为2...