(x+1)/(x-1)²+2/(x-1)=0两边乘(x-1)²x+1+2(x-1)=03x-1=0x=1/3经检验，x=1/3是方程的解
原式(x^2+x+1)/(x^2+1)+(x^2+1)/(x^2+x+1)=13/6令t=(x^2+x+1)/(x^2+1)则3/2>=t>=1/2所以原式t+1/t=13/6解得t=2/3或3/2即(x^2+x+1)/(x^2+1)=2/3或3/2解得x=1
