计算(1/2-1)×(1/3-1)×(1/3-1)×(1/4-1)×.×(1/2010-1)×(1/2011-1)等于多少?

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/12 02:32:59

计算(1/2-1)×(1/3-1)×(1/3-1)×(1/4-1)×.×(1/2010-1)×(1/2011-1)等于多少?
计算(1/2-1)×(1/3-1)×(1/3-1)×(1/4-1)×.×(1/2010-1)×(1/2011-1)等于多少?

计算(1/2-1)×(1/3-1)×(1/3-1)×(1/4-1)×.×(1/2010-1)×(1/2011-1)等于多少?
(1/2-1)×(1/3-1)×(1/4-1)×...×(1/2011-1)
=(1-1/2)(1-1/3)(1-1/4)...(1-1/2011)
=(1/2)(2/3)(3/4)...(2010/2011)
=(1×2×3×...×2010)/(2×3×4×...×2011)
=1/2011

怎么有两个(1/3-1)?如果都是两个就是
(1/2-1)×(1/3-1)×(1/3-1)×(1/4-1)×。。。×(1/2010-1)×(1/2011-1)
=(1/2)(2/3)(2/3)(3/4)(3/4)...(2010/2011)
=2/2011