已知:|x-2|+|y-4|=0,求:1/xy+1/(x+2)(y+2)+1/(x+4)(y+4)+……+1/(x+2010)(y+2010).要简便运算.

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已知:|x-2|+|y-4|=0,求:1/xy+1/(x+2)(y+2)+1/(x+4)(y+4)+……+1/(x+2010)(y+2010).要简便运算.已知:|x-2|+|y-4|=0,求:1/x

已知:|x-2|+|y-4|=0,求:1/xy+1/(x+2)(y+2)+1/(x+4)(y+4)+……+1/(x+2010)(y+2010).要简便运算.
已知:|x-2|+|y-4|=0,
求:1/xy+1/(x+2)(y+2)+1/(x+4)(y+4)+……+1/(x+2010)(y+2010).要简便运算.

已知:|x-2|+|y-4|=0,求:1/xy+1/(x+2)(y+2)+1/(x+4)(y+4)+……+1/(x+2010)(y+2010).要简便运算.
|x-2|+|y-4|=0,绝对值≥0,说明|x-2|=0;|y-4|=0.所以X=2 Y=4
1/xy+1/(x+2)(y+2)+1/(x+4)(y+4)+……+1/(x+2010)(y+2010)
=1/2*4+1/(2+2)(4+2)+1/(2+4)(4+4)+……+1/(2+2010)(4+2010)=1/(2*4)+1/(4*6)+1/(4*6)+……+1/(2012*2014)
=1/2[(1/2-1/4)+(1/4-1/6)+……+(1/2012-1/2014)
]=1/2*(1/2-1/2014)
=503/2014
于22点21分50秒上传过程详细绝对原创!

∵|X-2|=0,|y-2|=0,
所以X=2,Y=4。
所以原式=1/2x4+1/4x6+1/6x8+1+……+1/2012x2014
=(1/2-1/2014)÷2
=503/2014

已知:|x-2|+|y-4|=0,因为绝对值是非负数,两个非负数相加=0,必须这两个数都=0,
即x-2=0,x=2,y-4=0,y=4

1/xy+1/(x+2)(y+2)+1/(x+4)(y+4)+……+1/(x+2010)(y+2010).
=1/2*4 +1/4*6 +1/6*8+。。。+1/2012*2014
=1/2(1/2-1/4+1/4-1...

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已知:|x-2|+|y-4|=0,因为绝对值是非负数,两个非负数相加=0,必须这两个数都=0,
即x-2=0,x=2,y-4=0,y=4

1/xy+1/(x+2)(y+2)+1/(x+4)(y+4)+……+1/(x+2010)(y+2010).
=1/2*4 +1/4*6 +1/6*8+。。。+1/2012*2014
=1/2(1/2-1/4+1/4-1/6+1/6-1/8+。。。+1/2012-1/2014)
=1/2(1/2-1/2014)
=1006/4028

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