(1-1/2)*(1-1/3)*(1-1/4)…..*(1-1/2019)*(1-1/2020) 18/10/2021 Bởi Adeline (1-1/2)*(1-1/3)*(1-1/4)…..*(1-1/2019)*(1-1/2020)
$(1-\frac{1}{2}).(1-\frac{1}{3}).(1-\frac{1}{4})…..(1-\frac{1}{2019}).(1-\frac{1}{2020})$ $=\frac{1}{2}.\frac{2}{3}.\frac{3}{4}…..\frac{2018}{2019}.\frac{2019}{2020}$ $=\frac{1}{2020}$. Bình luận
Đáp án: Giải thích các bước giải: `(1-1/2)(1-1/3)(1-1/4)….(1-1/2019)(1-1/2020)` `=(1/2).(2/3).(3/4)…..(2018/2019).(2019/2020)`\ `=(1.2.3……2018.2019)/(2.3.4…….2020)` `=1/2020` Bình luận
$(1-\frac{1}{2}).(1-\frac{1}{3}).(1-\frac{1}{4})…..(1-\frac{1}{2019}).(1-\frac{1}{2020})$
$=\frac{1}{2}.\frac{2}{3}.\frac{3}{4}…..\frac{2018}{2019}.\frac{2019}{2020}$
$=\frac{1}{2020}$.
Đáp án:
Giải thích các bước giải:
`(1-1/2)(1-1/3)(1-1/4)….(1-1/2019)(1-1/2020)`
`=(1/2).(2/3).(3/4)…..(2018/2019).(2019/2020)`\
`=(1.2.3……2018.2019)/(2.3.4…….2020)`
`=1/2020`