x1=C或x2=1+2/(C-1)观察可知x=C是方程的一个根整理此方程得x^2-(C+2/(C-1)+1)x+(C+2/(C-1)+2)=0根据韦达定理x1+x2=C+2/(C-1)+1又x1=C所以x2=1+2/(C-1)