1/1*4 1/4*7 1/7*10 … 1/100*103的简便运算
1/1*4 1/4*7 1/7*10 … 1/100*103的简便运算
日期:2022-04-03 21:36:49 人气:1
裂项法:
1/1*4+1/4*7+1/7*10+ … +1/100*103
=1/3*(1-1/4+1/4-1/7+1/7-1/10+……+1/100-1/103)
=1/3*(1-1/103)
=1/3*102/103
=34/103
1/1*4+1/4*7+1/7*10+ … +1/100*103
=1/3*(1-1/4+1/4-1/7+1/7-1/10+……+1/100-1/103)
=1/3*(1-1/103)
=1/3*102/103
=34/103