1/x+1-3-x/x的平方-6x+9除以/x的平方+x/x-3
=1/(x+1)+(x-3)/(x-3)²÷x(x+1)/(x-3)
=1/(x+1)+1/x(x+1)
=(x+1)/x(x+1)
=1/x
如果本题有什么不明白可以追问,