1/1*3+1/3*5+1/5*7+...+1/2007+2009
来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:数学作业 时间:2024/07/24 03:36:03
1/1*3+1/3*5+1/5*7+...+1/2007+2009
说出那样做的原因哦
说出那样做的原因哦
![1/1*3+1/3*5+1/5*7+...+1/2007+2009](/uploads/image/z/12754075-67-5.jpg?t=1%2F1%2A3%2B1%2F3%2A5%2B1%2F5%2A7%2B...%2B1%2F2007%2B2009)
1/1*3+1/3*5+1/5*7+...+1/2007*2009
=1/2(1/1-1/3+1/3-1/5+1/5-1/7+.+1/2005-1/2007+1/2007-1/2009)
=1/2(1-1/2009)=1004/2009
=1/2(1/1-1/3+1/3-1/5+1/5-1/7+.+1/2005-1/2007+1/2007-1/2009)
=1/2(1-1/2009)=1004/2009
1-3+5-7+...+2007-2009=?
1/1* 3+1/3* 5+1/5 *7+ ... +1/2007* 2009,要有理由
1/1*3+1/3*5+1/5*7+.+1/2007*2009等于多少啊?
1/(1*3)+1/(3*5)+1/(5*7)+…+1/2007*2009等于几?
1/1*3+1/3*5+1/5*7+...+1/2007+2009
计算:1/1×3+1/3×5+1/5×7+……+1/2005×2007+1/2007×2009
1/(1*3)+1/(5*7)+1/(9*11).1/(2007*2009)
1+3+5+7+9+11.+2005+2007+2009
1+3+5+7+...+2003+2005+2007+2009+2011=?
1+ 3+ 5 +7+ 9 +.+2003+2005+2007+2009+2011
(-1)+3+(-5)+7+(-9)+...+(-2005)+2007+(-2009)=?
-1+3+(-5)+7(-9)+...+2003+(-2005)+2007+(-2009)