(1-1/2-1/3-······-1/2006 )*(1/2+1/3+1/4·····
来源:百度知道 编辑:UC知道 时间:2024/05/15 11:01:55
(1-1/2-1/3-······-1/2006 )*(1/2+1/3+1/4·····+1/2007)-(1-1/2-1/3-……-1/2007)*(1/2+1/3+1/4+……+1/2006)
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大虾帮忙~
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大虾帮忙~
可以设(1/2+1/3+1/4+……+1/2006)为a
(1-1/2-1/3-······-1/2006 )为b
原式=b*(a+1/2007)-(b-1/2007)*a
=ab+b/2007-ab+a/2007
=(1-1/2-1/3-······-1/2006 )/2007+(1/2+1/3+1/4+……+1/2006)/2007
=(1-1+1/2-1/2+1/3-......1/2006+1/2007)/2007+(1-1/2+1/2-1/3+......-1/2006+1/2007)/2007
=1/2007
(1/2+1/3+1/4+……+1/2006)为a
(1-1/2-1/3-······-1/2006 )为b
原式=b*(a+1/2007)-(b-1/2007)*a
=ab+b/2007-ab+a/2007
=(1-1/2-1/3-······-1/2006 )/2007+(1/2+1/3+1/4+……+1/2006)/2007
=(1-1+1/2-1/2+1/3-......1/2006+1/2007)/2007+(1-1/2+1/2-1/3+......-1/2006+1/2007)/2007
=1/2007
(1+1/2+1/3+1/4)×
(1-1/2)(1-1/3)(1-1/4)(1-1/5).....(1-1/1000)
1+1/2+1+1/3+1+1/4+......+1/100=?
(1+1/2)(1+1/2^2)(1+1/2^4)(1+1/2^8)
(1-1/2^2)*(1-1/3^2)*(1-1/4^2).......(1-1/100^2)
1/1+1/2+1/3+1/4+。。。。+1/N 是多少
1/1+1/2+1/3+1/4+......1/2002=?
1-1/2+1/3-1/4+........1/99-1/100
求和Sn=1+(1+1/2)+(1+1/2+1/4)+....+[1+1/2+1/4.....+1/2^(n-1)]
数列 1+(1+1/2)+(1+1/2+1/4)+..............=?