m=1 mn=2 1/mn+1/(n+1)(m+1)+1/(n+2)(m+2)+1/(n+3)(m+3)...+1/(n

来源：学生作业帮编辑：作业帮分类：数学作业时间：2024/11/06 00:47:40

m=1 mn=2
1/mn+1/(n+1)(m+1)+1/(n+2)(m+2)+1/(n+3)(m+3)...+1/(n+2010)(m+2010)
=多少?

因为:m=1 mn=2,所以:m=1 n=2/m=2,
把m=1,n=2代入下面式子中,便可得解.
即为:1/1*2+1/(2*3)+1/(3*4)...+1/(2011*2012)
发现没有1/2=1/1-1/2
1/(2*3)=1/2-1/3
1/(3*4)=1/3-1/4依此类推,
1/(2011*2012)=1/2011-1/2022
所以原式=1/2+1/2-1/3+1/3-1/4+1/4-1/5...+1/2010-1/2011+1/2011-1/2012,中间是抵销了,=1-1/2012
=2011/2012

已知m-n=3,mn=-1,求多项式-2mn+2m+3n-3mn-2n+2m-4n-m-mn的值已知m-n=2,mn=1,求多项式(2mn+2m+3n)-(3mn+2n-2m)-(m+4n+mn)的值若m-n=4,mn=-1求(9-2mn+2m+3n)-(3mn+2n-2m)-(m+4n+mn) 若m-n=4,mn=-1,求(-2mn+2m+3n)-(3mn+2n-2m)-(m+4n+mn)的值若m-n=4,mn=-1,求(-2mn+m+n)-(3mn+5n-5m)-(m+4n-3mn)的值知m*m-mn=1,4mn-3n*n=-2,则m*m+3mn-3n*n的值是多少 m(m+n)(m-n)-m(m+n)的平方,其中m+n=1,mn=-1/2 已知1/m-1/n=2,试求(3m+mn-3n)/(m-mn-n)的值已知｜m-n-2｜与（mn-1)^互为相反数,求（-2mn+2m+3n)-(3mn+2n-2m)-(m+4n+mn)的值 -2(mn-3m平方)-{m平方-5(mn-m平方)+2mn,其中m=1,n=-2 先化简（m/m-n-n/m+n+2mn/m²-n²)²÷m²+mn/m,若m=1 m=1 mn=2 1/mn+1/(n+1)(m+1)+1/(n+2)(m+2)+1/(n+3)(m+3)...+1/(n