1+1/(x+2)+1+1/(x+3)=1+1/(x+4)+1+1/(x+1)
1/(x+2)+1/(x+3)=1/(x+4)+1/(x+1)
1/(x+3)-1/(x+4)=1/(x+1)-1/(x+2)
1/(x+3)(x+4)=1/(x+1)(x+2)
(x+1)(x+2)=(x+3)(x+4)
x²+3x+2=x²+7x+12
x=-5/2
检验:x=-5/2是方程的解
1+1/(x+2)+1+1/(x+3)=1+1/(x+4)+1+1/(x+1)
1/(x+2)+1/(x+3)=1/(x+4)+1/(x+1)
1/(x+3)-1/(x+4)=1/(x+1)-1/(x+2)
1/(x+3)(x+4)=1/(x+1)(x+2)
(x+1)(x+2)=(x+3)(x+4)
x²+3x+2=x²+7x+12
x=-5/2
检验:x=-5/2是方程的解