x²+2x+2=6/(x+1)²(x+1)²+1=6/(x+1)²令t=(x+1)²,则：t≧0原方程化为：t+1=6/tt²+t-6=0(t+3)(t-2)=0t1=-3（舍去）t2=2即：(x+1)²=2x+1=±√2x=-1±√2即：x1=-1-√2,x2=-1+√2...