来自戴亚平的问题
【一道简单的数学趣味计算题计算1/a(a+1)+1/(a+1)(a+2)+1/(a+2)(a+3)+……+1/(a+2004)(a+2005)】
一道简单的数学趣味计算题
计算1/a(a+1)+1/(a+1)(a+2)+1/(a+2)(a+3)+……+1/(a+2004)(a+2005)
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2020-05-16 08:25
【一道简单的数学趣味计算题计算1/a(a+1)+1/(a+1)(a+2)+1/(a+2)(a+3)+……+1/(a+2004)(a+2005)】
一道简单的数学趣味计算题
计算1/a(a+1)+1/(a+1)(a+2)+1/(a+2)(a+3)+……+1/(a+2004)(a+2005)
1/a(a+1)=1/a-1/(a+1)1/a(a+1)+1/(a+1)(a+2)+1/(a+2)(a+3)+……+1/(a+2004)(a+2005)=1/a-1/(a+1)+1/(a+1)-1/(a+2)+……+1/(a+2004)-1/(a+2005)=1/a-1/(a+2005)=2005/a(a+2005)