x^2+2x+2=6/(x+1)^2
(x+1)^2 +1=6/(x+1)^2
设(x+1)^2=y
y+1=6/y
y^2+y-6=0
(y+3)(y-2)=0
y=-3(舍去)
y=2
(x+1)^2=2
x+1=±√2
x1=√2-1
x1=-√2-1