1/6+1/12+1/24+...+1/768
1/6 + 1/12 + 1/24+... + 1/768
1/6+1/12+1/24+...+1/768
Gọi tổng đó là A
A = 1/6+1/12+1/24+...+1/768
A x 2 = 1/3 + 1/6 + 1/12 + 1/24 + .... + 1/384
A x 2 - A = 1/3 + 1/6 + 1/12 + 1/24 + .... + 1/384 - 1/6 + 1/12 + 1/24 + ... + 1/768
A = 1/3 - 1/768 = 85/256
Gọi tổng đó là Z
Z = 1/6+1/12+1/24+...+1/768
Z . 2 = 1/3 + 1/6 + 1/12 + 1/24 + .... + 1/384
Z . 2 - A = 1/3 + 1/6 + 1/12 + 1/24 + .... + 1/384 - 1/6 + 1/12 + 1/24 + ... + 1/768
Z = 1/3 - 1/768 = 85/256
1/6+1/12+1/24+....+1/768
1-2 / 3-1 / 6-1 / 12-1 / 24-1 / 48 - ...... 1/768
= 1 / 3-1 / 6-1 / 12-1 / 24-1 / 48 - ...... 1/768
= 1 / 6-1 / 12-1 / 24-1 / 48 - ...... 1/768
= 1 / 12-1 / 24-1 / 48 - ...... 1/768
= 1 / 24-1 / 48- ...... 1/768
= 1/768
kết bạn và k với mình nha cảm ơn bạn và các bạn khác ủng hộ cho mình
1/3+1/6+1/12+1/24+....+1/768+1/1536
1/3+1/6+1/12+1/24+....+1/768+1/1536
\(A=\dfrac{1}{3}\left(1+\dfrac{1}{2}+...+\dfrac{1}{256}+\dfrac{1}{512}\right)\)
Đặt B=1+1/2+...+1/256+1/512
=>2B=2+1+...+1/128+1/256
=>B=2-1/512=1023/512
=>\(A=\dfrac{1}{3}\cdot\dfrac{1023}{512}=\dfrac{341}{512}\)
1/6 + 1/12 + 1/24 + ....+ 1/768 = ...............
A=1/3 + 1/6 + 1/12 +1/24 + ............+ 1/768 + 1/1536
1/3+1/6+1/12+1/24+....1/768
đúng sẽ đc likeAAAAAAAAAAAAAAAAAAA
A = 1/3 + 1/6 + 1/12 + 1/24 + 1/48 + 1/96 + 1/192 + 1/384 + 1/768 +1/1536
\(A=\frac{1}{3}+\frac{1}{6}+\frac{1}{12}+\frac{1}{24}+\frac{1}{48}+\frac{1}{96}+\frac{1}{192}+\frac{1}{384}+\frac{1}{768}+\frac{1}{1536}\)
\(A\times2=\frac{2}{3}+\frac{2}{6}+\frac{2}{12}+\frac{2}{24}+\frac{2}{48}+\frac{2}{96}+\frac{2}{192}+\frac{2}{384}+\frac{2}{768}+\frac{2}{1536}\)
Rút gọn ta được
\(A\times2=\frac{2}{3}+\frac{1}{3}+\frac{1}{6}+\frac{1}{12}+\frac{1}{24}+\frac{1}{48}+\frac{1}{96}+\frac{1}{192}+\frac{1}{384}+\frac{1}{768}\)
\(A\times2-A=\frac{2}{3}+\frac{1}{3}+\frac{1}{6}+...+\frac{1}{768}-\left[\frac{1}{3}+\frac{1}{6}+...+\frac{1}{1536}\right]\)
\(A=\frac{2}{3}+\frac{1}{3}-\frac{1}{3}-\frac{1}{1536}\)
\(A=\frac{2}{3}-\frac{1}{1536}=\frac{341}{512}\)
Bạn hiểu cách làm lớp 6 ko mk gửi