国电瑞驰什么:请看问题补充说明 谢谢!

来源:百度文库 编辑:查人人中国名人网 时间:2024/05/05 01:10:44
先化简,再求值:[(1/(x-y))+(1/(x+y))]除以xy/(x^2-y^2).其中x=根号3减根号2,y=根号2.
=[(2X/(X+Y)*(X-Y)]*)我的确看不懂 请说清楚些!!谢谢

=[(2X/(X+Y)*(X-Y)]*)他们的这一步好象行不通 你的慎重些

根号2

解:原式=[1/(X+Y)+1/(X-Y)]*(X^2-Y^2)/XY
=[(2X/(X+Y)*(X-Y)]*)*(X+Y)*(X-Y)//XY
=2/Y
=根号2

解:原式=[1/(X+Y)+1/(X-Y)]*(X^2-Y^2)/XY
=[(2X/(X+Y)*(X-Y)]*)*(X+Y)*(X-Y)//XY
=2/Y
=根号2
你怎么抢我答案,怎么是一样的呢?