A= 1/39-1/6-1/56
__________________:31/6
1/8-1/52+1/68
\(B=\frac{\frac{1}{39}-\frac{1}{6}-\frac{1}{51}}{\frac{1}{8}-\frac{1}{52}+\frac{1}{68}}:\frac{31}{6}\)
\(B=\frac{\frac{1}{39}-\frac{1}{6}-\frac{1}{51}}{\frac{1}{8}-\frac{1}{52}+\frac{1}{68}}:\frac{31}{6}\)
\(=\frac{\frac{1}{3}\left(\frac{1}{13}-\frac{1}{2}-\frac{1}{17}\right)}{\frac{1}{4}\left(\frac{1}{2}-\frac{1}{13}+\frac{1}{17}\right)}.\frac{6}{31}\)
\(=\frac{\frac{-1}{3}\left(\frac{-1}{13}+\frac{1}{2}+\frac{1}{17}\right)}{\frac{1}{4}\left(\frac{1}{2}-\frac{1}{13}+\frac{1}{17}\right)}.\frac{6}{31}\)
\(=\frac{-1}{3}:\frac{1}{4}.\frac{6}{31}\)
\(=\frac{-1}{3}.4.\frac{6}{31}\)
Tiếp theo dễ r tự làm tiếp :)
Tính :\(\frac{\frac{1}{39}-\frac{1}{6}-\frac{1}{51}}{\frac{1}{8}-\frac{1}{52}-\frac{1}{68}}:\frac{31}{6}\)
SỐ LẺ NHA BẠN - \(\frac{1704}{4991}\)
Cách giải bạn có thể hướng dẫn mk ko cảm ơn bạn nhiều!
Thực hiện phép tính
a) A= [6×(1/3)^3-3(-1/3)+1] : (-1/3-1)
b) B= (1/39-1/6-1/51)/(1/8-1/52+1/68)
\(A=\left[6.\left(\frac{1}{3}\right)^3-3\left(\frac{-1}{3}\right)+1\right]:\left(\frac{-1}{3}-1\right)\)
\(A=\left[6.\frac{1}{27}-3.\left(\frac{-1}{3}\right)+1\right]:\left(\frac{-1}{3}-1\right)\)
\(A=\left[\frac{2}{9}-\frac{-3}{3}+\frac{9}{9}\right]:\left(\frac{-1}{3}+\frac{-3}{3}\right)\)
\(A=\frac{2}{9}.\frac{-3}{4}=\frac{1}{3}.\frac{-1}{2}=\frac{-1}{6}\)
tính: A=1/6-1/39+1/51 / 1/8-1/52+1/68 B=512-512/2-512/2^2-512/2^3-...-512/2^10
?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????/??bố thằng nào mà biết được
\(\dfrac{\dfrac{1}{6}-\dfrac{1}{39}+\dfrac{1}{51}}{\dfrac{1}{8}-\dfrac{1}{52}+\dfrac{1}{68}}\)
\(\dfrac{\dfrac{1}{6}-\dfrac{1}{39}+\dfrac{1}{51}}{\dfrac{1}{8}-\dfrac{1}{52}+\dfrac{1}{68}}\)
\(\dfrac{11}{\dfrac{78}{\dfrac{11}{104}+\dfrac{1}{68}}}+\dfrac{1}{51}\)
\(\dfrac{71}{\dfrac{442}{\dfrac{213}{1768}}}\)\(\Rightarrow\dfrac{4}{3}\)
Tính nhanh:\(B=\frac{\frac{1}{39}-\frac{1}{6}-\frac{1}{51}}{\frac{1}{8}-\frac{1}{52}+\frac{1}{68}}:5\frac{1}{6}\)
Ta có : \(B=\frac{\frac{1}{39}-\frac{1}{6}-\frac{1}{51}}{\frac{1}{8}-\frac{1}{52}+\frac{1}{68}}:5\frac{1}{6}\)
=> \(B=\frac{\frac{\frac{1}{13}-\frac{1}{2}-\frac{1}{17}}{3}}{\frac{\frac{1}{2}-\frac{1}{13}+\frac{1}{17}}{4}}:5\frac{1}{6}\)
=> \(B=\frac{\frac{\frac{1}{13}-\frac{1}{2}-\frac{1}{17}}{3}}{\frac{\frac{1}{13}-\frac{1}{2}-\frac{1}{17}}{-4}}:5\frac{1}{6}\)
=> \(B=\frac{-4}{3}:5\frac{1}{6}\)
=> \(B=\frac{-8}{6}:\frac{31}{6}=-\frac{8}{6}.\frac{6}{31}=-\frac{8}{31}\)
tính: \(\frac{\frac{1}{6}-\frac{1}{39}+\frac{1}{51}}{\frac{1}{8}-\frac{1}{52}+\frac{1}{68}}\)
Ta có: \(\frac{\frac{1}{6}-\frac{1}{39}+\frac{1}{51}}{\frac{1}{8}-\frac{1}{52}+\frac{1}{68}}=\frac{\left(\frac{1}{6}-\frac{1}{39}+\frac{1}{51}\right).5304}{\left(\frac{1}{8}-\frac{1}{52}+\frac{1}{68}\right).5304}\)\(=\frac{136-884+104}{663-102+78}=-\frac{664}{639}\)
tính A=1/6-1/39+1/51 / 1/8-1/52+1/68 ; B= 512-512/2-512/2^2-212/2^3-...-512/2^10
1) Tính \(\frac{\frac{1}{39}-\frac{1}{6}-\frac{1}{51}}{\frac{1}{8}-\frac{1}{52}+\frac{1}{68}}\)
Ta có : \(\frac{\frac{1}{39}-\frac{1}{6}-\frac{1}{51}}{\frac{1}{8}-\frac{1}{52}+\frac{1}{68}}=\frac{\left(\frac{1}{39}-\frac{1}{6}-\frac{1}{51}\right)\times5304}{\left(\frac{1}{8}-\frac{1}{52}+\frac{1}{68}\right)\times5304}=\frac{136-884-104}{663-102+78}=\frac{-852}{639}=-\frac{4}{3}\)