【{x²-4x+4/x²-4}-x/x+2】÷x-1/x+2

问题描述:

【{x²-4x+4/x²-4}-x/x+2】÷x-1/x+2

=((x-2)2/(x+2)(x-2)-x/(x+2)÷x-1/x+2
=((x-2)/(x+2)-x/x+2)÷x-1/x+2
=-2/x+2*x+2/x-1
=-2/x-1

【{x²-4x+4/x²-4}-x/x+2】÷x-1/x+2=【{(X-2)/(X+2)}-{X(X+2)/X+2}/(X+2)】÷{x-1/x+2}=
【{-(X-1)}/(X+2)】÷{(X-1)/(X+2)}=【{-(X-1)}/(X+2)】*{(X+2)/(X-1)}=-1