化简:1/xy+1/(x+4)(y+4)+1/(x+8)(y+8)+1/(x+12)(y+12)+.1/(x+4n)(y+4n)y=10 x=4 y=2 x=4 y=8 x=4

来源:学生作业帮助网 编辑:作业帮 时间:2024/11/17 03:42:11

化简:1/xy+1/(x+4)(y+4)+1/(x+8)(y+8)+1/(x+12)(y+12)+.1/(x+4n)(y+4n)y=10 x=4 y=2 x=4 y=8 x=4
化简:1/xy+1/(x+4)(y+4)+1/(x+8)(y+8)+1/(x+12)(y+12)+.1/(x+4n)(y+4n)
y=10 x=4 y=2 x=4 y=8 x=4

化简:1/xy+1/(x+4)(y+4)+1/(x+8)(y+8)+1/(x+12)(y+12)+.1/(x+4n)(y+4n)y=10 x=4 y=2 x=4 y=8 x=4
1/xy=(1/x-1/y)*(1/y-x)
1/(x+4)(y+4)=(1/(x+4)-1/(y+4))*(1/y-x)
提取(1/y-x) 原式=( 1/y-x)*(1/x-1/y+1/(x+4)-1/(y+4).1/(x+4n)-1/(y+4n))
因为x=4,y=8
所以 原式=(1/4)*( 1/4 -1/8+1/8 -1/12.1/(4+4n) -1/(8+4n))
=(1/4)*(1/4-1/(8+4n))
=(n+1)/(32+16n)
对x=4,y=10和y=2,x=4类似套就可以了

1xy+1x4+y+4+1………………………………………………4n+y. 你确定,这是题目吗?额,我想晕倒!难道这是高中的题?

无法化简

补充是什么意思??

哇卡,,我们初中老师让我们做,,
我们那道题没有补充的。。。

x=y=4 我做不出
x=4,y=8 我做出le
1/xy=(1/x-1/y)*(1/y-x)
1/(x+4)(y+4)=(1/(x+4)-1/(y+4))*(1/y-x)
......以此推类
提取(1/y-x) 原式=( 1/y-x)*(1/x-1/y+1/(x+4)-1/(y+4)......1/(x+4n)-1/(y+4n))
因为x=4,...

全部展开

x=y=4 我做不出
x=4,y=8 我做出le
1/xy=(1/x-1/y)*(1/y-x)
1/(x+4)(y+4)=(1/(x+4)-1/(y+4))*(1/y-x)
......以此推类
提取(1/y-x) 原式=( 1/y-x)*(1/x-1/y+1/(x+4)-1/(y+4)......1/(x+4n)-1/(y+4n))
因为x=4,y=8
所以 原式=(1/4)*( 1/4 -1/8+1/8 -1/12......1/(4+4n) -1/(8+4n))
=(1/4)*(1/4-1/(8+4n))
=(n+1)/(32+16n)
希望能给你点思路
也希望给我点分。。。。。。

收起

x=4,y=8

求帮助,我也正在困扰该题目。。。