先化简再求值（1-1/x+2）÷x²-1/x+2其中x=2写出具体步骤!

先化简再求值（1-1/x+2）÷x²-1/x+2其中x=2写出具体步骤!
先化简再求值（1-1/x+2）÷x²-1/x+2其中x=2写出具体步骤!

先化简再求值（1-1/x+2）÷x²-1/x+2其中x=2写出具体步骤!
原式=[1-1/(x+2)]÷[(x²-1)/(x+2)]
=[(x+2)/(x+2)-1/(x+2)]÷[(x+1)(x-1)/(x+2)]
=[(x+1)/(x+2)]×{(x+2)/[(x+1)(x-1)]}
=1/(x-1)
=1/(2-1)
=1

如图: