作业帮0.2008加2.008加20.08加200.8加2008
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/14 14:21:22
12342
1/2-1/3+1/3-1/4……+1/9-1/10=1/2-1/10=2/5
1/6=（1/2)*(1/3),1/12=(1/3)*(1/4),1/20=(1/4)*(1/5),1/30=(1/5)*(1/6),1/42=(1/6)*(1/7),1/56=(1/7)*(1/8)
仔细看就会发现1／6=1／2-1／3,1／12=1／3-1／4...它们是有规律的原式=1+12+1／2-1／3+1／3-1／4+1／4-1／5+1／5-1／6+1／6-1／7+1／7-1／8+1／8
1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90=1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1
1/3+3/4+2/5+5/7+7/8+9/20+10/21+11/24+19/35=1/3+3/4+2/5+5/7+7/8+(4/20+5/20)+(3/21+7/21)+(3/24+8/24)+(
1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90=(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+(1/5-1/6)+(1/6-1/7)+(1/7-1/8)+(
=1/1×2+1/2×3+1/3×4+1/4×5+1/5×6+1/6×7+1/7×8+1/8×9+1/9×10=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/
104再问：和你相互采纳怎样？？？？再问：我发十个贴。只采纳你。再问：你发十个贴。只采纳我。再问：怎样？再问：^_-
1/2+1/2-1/3+1/3-1/4+1/4-1/5+.-.-1/10=9/10求最佳!
32.8+20+18.8=71.6
250,
(x-1)(x+2)(x+3)(x+6)+20=0(x-1)(x+6)(x+2)(x+3)+20=0(x^2+5x-6)(x^2+5x+6)+20=0(x^2+5x)^2-36+20=0(x^2+5x
1+3+5+……+19+21=121=11的平方
5+9+6+20=40
4100再问：错啦
1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72=1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9=1/
=1/1×2+1/2×3+1/3×4+……+1/2010×2011=1-1/2+1/2-1/3+1/3-1/4+……+1/2010-1/2011=1-1/2011=2010/2011
二分之一加6分之一加12分之一加20分之一加30分之一加42分之一加五十六分之一=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8=1-1/8