(1) 1 1×2 + 1 2×3 + 1 3×4 +…+
来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/05/24 02:26:24
(1)
1 1×2 + 1 2×3 + 1 3×4 +…+ 1 2004×2005 + 1 2005×2006 =1- 1 2 + 1 2 - 1 3 + 1 3 - 1 4 +…+ 1 2005 - 1 2006 =1- 1 2006 = 2005 2006 ; (2) 1 1×3 + 1 3×5 + 1 5×7 +…+ 1 49×51 = 1 2 ×(1- 1 3 + 1 3 - 1 5 +…+ 1 49 - 1 51 ) = 1 2 ×(1- 1 51 ) = 1 2 × 50 51 = 25 51 .
(1/1+2)+(1/1+2+3)+(1/1+2+3+4)+………+(1/1+2+3+………+100)
(1/2+1/3+1/4+…+2002)*(1+1/2+1/3+1/4+…1/2001)-
1+1\(1+2)+1\(1+2+3)+1\(1+2+3+4)+……1\(1+2+3+……2010)
(1-1/2-1/3-1/4-……-1/2003)(1/2+1/3+1/4+...+1/2004)-(1-1/2-1/3
计算:(1/2+1/3+1/4+…+1//2006)(1+1/2+1/3+…+1/2005)-(1+1/2+1/3+1/
初中计算题,难(1-1/2-1/3-……-1/2008)*(1/2+1/3+1/4+……+1/2009)-(1-1/2-
(-1×1/2)+(-1/2×1/3)+(-1/3×1/4)+…+(-1/2008×1/2009)
1/(1+2) + 1/(1+2+3) + 1/(1+2+3+4)……+1/(1+2+3+4+……+99+100)=(
1/(1-1/2)/(1-1/3)/(1-1/4)/……/(1-1/2012)
用简便算法计算:(1-1/2-1/3-1/4-…-1/2010)×(1/2+1/3+1/4+…+1/2010)-(1-1
(1-1/2)*(1-1/3)*(1-1/4)*……*(1-1/100)
(1-1/2)*(1-1/3)*(1-1/4)*……*(1-1/9) 算式
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