Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
5: \(=\dfrac{43}{8}-\dfrac{19}{10}=\dfrac{430}{80}-\dfrac{152}{80}=\dfrac{278}{80}=\dfrac{139}{40}\)
6: \(=\dfrac{-13}{4}-\dfrac{7}{3}=\dfrac{-39}{12}-\dfrac{28}{12}=\dfrac{-67}{12}\)
7: \(=\dfrac{-41}{8}+\dfrac{14}{4}=\dfrac{-41}{8}+\dfrac{28}{8}=\dfrac{-13}{8}\)
8: \(=\dfrac{-43}{7}+\dfrac{-43}{6}=\dfrac{-559}{42}\)
5, \(5\dfrac{3}{8}-1\dfrac{9}{10}=\dfrac{139}{40}\)
6, \(\left(-3\dfrac{1}{4}\right)+\left(-2\dfrac{1}{3}\right)=-\dfrac{67}{12}\)
7, \(\left(-5\dfrac{1}{8}\right)+3\dfrac{2}{4}=-\dfrac{13}{8}\)
8, \(\left(-6\dfrac{1}{7}\right)+\left(-7\dfrac{1}{6}\right)=-\dfrac{559}{42}\)
\(A=\frac{1}{3.5}+\frac{1}{5.7}+\frac{1}{7.9}+...+\frac{1}{37.39}\)
\(2.A=\frac{2}{3.5}+\frac{2}{5.7}+\frac{2}{7.9}+...+\frac{2}{37.39}\)
\(2.A=\frac{1}{3}-\frac{1}{5}+\frac{1}{5}-\frac{1}{7}+\frac{1}{7}-\frac{1}{9}+...+\frac{1}{37}-\frac{1}{39}\)
\(2.A=\frac{1}{3}-\frac{1}{39}\)
\(2.A=\frac{13}{39}-\frac{1}{39}=\frac{12}{39}=\frac{4}{13}\)
\(A=\frac{4}{13}:2=\frac{4}{13}.\frac{1}{2}=\frac{2}{13}\)
\(B=\frac{1}{3.4}+\frac{1}{4.5}+\frac{1}{5.6}+...+\frac{1}{95.96}\)
\(B=\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+\frac{1}{5}-\frac{1}{6}+...+\frac{1}{95}-\frac{1}{96}\)
\(B=\frac{1}{3}-\frac{1}{96}\)
\(B=\frac{32}{96}-\frac{1}{96}=\frac{31}{96}\)
`#` `\text{dkhanhqlv}`
`a)1/8-1/2`
`=1/8-4/8`
`=-3/8`
`b)-11/12-(-1)`
`=-11/12+1`
`=-11/12+12/12`
`=1/12`
`c)3/5-5/6`
`=18/30-25/30`
`=-7/30`
`d)-1/16-1/15`
`=-15/240-16/240`
`=-31/240`
`e)11/36-(-7/24)`
`=11/36+7/24`
`=22/72+21/72`
`=43/72`
`g)-5/9-(-5/12)`
`=-5/9+5/12`
`=-20/36+15/36`
`=-5/36`
a) \(\dfrac{1}{8}-\dfrac{1}{2}=\dfrac{1}{8}-\dfrac{4}{8}=-\dfrac{3}{8}\)
b) \(-\dfrac{11}{12}-\left(-1\right)=-\dfrac{11}{12}+\dfrac{12}{12}=\dfrac{1}{12}\)
c) \(\dfrac{3}{5}-\dfrac{5}{6}=\dfrac{18}{30}-\dfrac{25}{30}=-\dfrac{7}{30}\)
d) \(-\dfrac{1}{16}-\dfrac{1}{15}=-\dfrac{15}{240}-\dfrac{16}{240}=-\dfrac{31}{240}\)
e) \(\dfrac{11}{36}-\left(-\dfrac{7}{24}\right)=\dfrac{11}{36}+\dfrac{7}{24}=\dfrac{22}{72}+\dfrac{21}{72}=\dfrac{43}{72}\)
g) \(-\dfrac{5}{9}-\left(-\dfrac{5}{12}\right)=-\dfrac{5}{9}+\dfrac{5}{12}=-\dfrac{20}{36}+\dfrac{15}{36}=-\dfrac{5}{36}\)
a: \(=\dfrac{-5}{8}+\dfrac{7}{12}=\dfrac{-15}{24}+\dfrac{14}{24}=\dfrac{-1}{24}\)
b: \(=\dfrac{3}{4}-\dfrac{5}{6}+\dfrac{11}{12}=\dfrac{9}{12}-\dfrac{10}{12}+\dfrac{11}{12}=\dfrac{10}{12}=\dfrac{5}{6}\)
c: \(=\dfrac{6}{36}-\dfrac{1}{36}=\dfrac{5}{36}\)
d: \(=\dfrac{5}{12}+\dfrac{5}{12}=\dfrac{10}{12}=\dfrac{5}{6}\)
e: \(=\dfrac{-8}{56}-\dfrac{7}{56}=\dfrac{-15}{56}\)
f: \(=\dfrac{-5}{15}+\dfrac{3}{25}=\dfrac{-25}{75}+\dfrac{9}{75}=\dfrac{-16}{75}\)
a: \(\dfrac{3}{5}-\left(-\dfrac{1}{2}\right)=\dfrac{3}{5}+\dfrac{1}{2}=\dfrac{6+5}{10}=\dfrac{11}{10}\)
b: \(-\dfrac{48}{96}+\dfrac{37}{148}\)
\(=-\dfrac{1}{2}+\dfrac{1}{4}=\dfrac{-2}{4}+\dfrac{1}{4}=-\dfrac{1}{4}\)
c: \(\dfrac{1}{5}+\dfrac{-1}{6}+\dfrac{1}{7}+\dfrac{-1}{8}+\dfrac{1}{9}+\dfrac{1}{8}+\dfrac{-1}{7}+\dfrac{1}{6}+\dfrac{-1}{5}\)
\(=\left(\dfrac{1}{5}-\dfrac{1}{5}\right)+\left(-\dfrac{1}{6}+\dfrac{1}{6}\right)+\left(\dfrac{1}{7}-\dfrac{1}{7}\right)+\left(-\dfrac{1}{8}+\dfrac{1}{8}\right)+\dfrac{1}{9}\)
\(=0+0+0+0+\dfrac{1}{9}=\dfrac{1}{9}\)