bằng-1/5

\(\frac{-5}{7}+\frac{3}{4}+\frac{-1}{5}+\frac{-2}{7}+\frac{1}{4}\)

\(=\left(\frac{-5}{7}+\frac{-2}{7}\right)+\left(\frac{3}{4}+\frac{1}{4}\right)+\frac{-1}{5}\)

\(=-1+1+\frac{-1}{5}\)

\(=-\frac{1}{5}\)

\(\frac{\frac{1}{9}-\frac{5}{6}-4}{\frac{7}{12}-\frac{1}{36}-10}=\frac{36.\left(\frac{1}{9}-\frac{5}{6}-4\right)}{36.\left(\frac{7}{12}-\frac{1}{36}-10\right)}\)

                             \(=\frac{4-6.5-36.4}{3.7-1-36.10}\)

                               \(=\frac{4-30-144}{21-1-360}\)

                               \(=\frac{-26-144}{20-360}=\frac{-170}{-340}=\frac{1}{2}\)

\(\frac{\frac{4}{36}-\frac{30}{36}-\frac{144}{36}}{\frac{21}{36}-\frac{1}{36}-\frac{360}{36}}=\frac{\frac{-170}{36}}{\frac{-340}{36}}=\frac{-170}{36}:\frac{-340}{36}=\frac{-170}{36}.\frac{36}{-340}=\frac{-170}{-340}=\frac{1}{2}\)

Bấm máy tính là ra ^0^

a, \(\left(\frac{1}{5}-\frac{1}{4}\right)^2=\left(\frac{-1}{20}\right)^2=\frac{1}{400}\)

b, \(\left(\frac{5}{3}+\frac{1}{2}\right):\frac{-13}{5}+1\frac{5}{6}\)

=> \(\frac{13}{6}:\frac{-13}{5}+\frac{11}{6}\)

=> \(\frac{13}{6}.\frac{5}{-13}+\frac{11}{6}\)

=> \(\frac{-5}{6}+\frac{11}{6}=\frac{6}{6}=1\)

c, \(\left(\frac{3}{17}\right)^4.\left(\frac{-17}{6}\right)^4\)

=> \(\left(\frac{3}{17}.\frac{-17}{6}\right)^4=\left(\frac{-1}{2}\right)^4=\frac{1}{16}\)

đúng 100%

a) \(\left(\frac{1}{5}-\frac{1}{4}\right)^2=\left(-\frac{1}{20}\right)^2=\frac{1}{400}.\)

b) \(\left(\frac{5}{3}+\frac{1}{2}\right):-\frac{13}{5}+1\frac{5}{6}\)

= \(\frac{13}{6}:\left(-\frac{13}{5}\right)+\frac{11}{6}\)

= \(\left(-\frac{5}{6}\right)+\frac{11}{6}\)

= \(1.\)

c) \(\left(\frac{3}{17}\right)^4.\left(-\frac{17}{6}\right)^4\)

= \(\left[\frac{3}{17}.\left(-\frac{17}{6}\right)\right]^4\)

= \(\left(-\frac{1}{2}\right)^4=\frac{1}{16}.\)

Chúc bạn học tốt!

a)(1/4+3/4)-(5/13+8/13)+2/11=1-1+2/11=2/11

b)(21/31+10/31)-16/7+(44/53+9/53)=1+1-16/7=14/7-16/7=-2/7

bằng2/11

         -16/7

a, \(\left(\frac{1}{4}+\frac{-5}{13}\right)+\left(\frac{2}{11}+\frac{-8}{13}+\frac{3}{4}\right)\)

\(=\left(\frac{1}{4}-\frac{5}{13}\right)+\left(\frac{2}{11}-\frac{8}{13}+\frac{3}{4}\right)\)

\(=\frac{1}{4}-\frac{5}{13}+\frac{2}{11}-\frac{8}{13}+\frac{3}{4}=1-1+\frac{2}{11}=\frac{2}{11}\)( vì \(\left(\frac{1}{4}+\frac{3}{4}\right)+\left(-\frac{5}{13}-\frac{8}{13}+\frac{2}{11}\right)\))

b, \(\left(\frac{21}{31}+\frac{-16}{7}\right)+\left(\frac{44}{53}+\frac{10}{31}\right)+\frac{9}{53}\)

\(=\frac{21}{31}-\frac{16}{7}+\frac{44}{53}+\frac{10}{31}+\frac{9}{53}\)

\(=1-\frac{16}{7}+1=\frac{7}{7}-\frac{16}{7}+\frac{7}{7}=-\frac{2}{7}\)

âm 2( số -2) và 4/25

\(\frac{-3}{31}+\frac{-6}{17}+\frac{1}{25}+\frac{-28}{31}+\frac{-11}{17}+\frac{-1}{5}\)

\(=\left(\frac{-3}{31}+\frac{-28}{31}\right)+\left(\frac{-6}{17}+\frac{-11}{17}\right)+\left(\frac{1}{25}+\frac{-1}{5}\right)\)

\(=\frac{-31}{31}+\frac{-17}{17}+\frac{-4}{25}\)

\(=\left(-1\right)+\left(-1\right)+\frac{-4}{25}\)

\(=\frac{\left(-25\right)+\left(-25\right)+\left(-4\right)}{25}\)

\(=\frac{-54}{25}\)

(-3/31+-28/31)+(6/17+11/17)+1/25+-1/5

-1+-1+1/25 +-1/5

-2+1/25+-1/5

-2/1+1/25+-1/5

-50/25+1/25+-5/25

-49/25+-5/25

-54/25

mik đúng mn k  cho mik nha cảm ơn mn

1/2 . ( 2/9 + 3/7 - 5/27 )

=1/2 . ( 2/9-5/27)+3/7

=1/2 . (1/27+3/7)

=1/2 .

=1/2x88/189=44/189

\(\frac{1}{2}\times\left(\frac{2}{9}+\frac{3}{7}-\frac{5}{21}\right)\)

\(=\frac{1}{2}\times\frac{88}{189}\)

\(=\frac{44}{189}\) 

Học Tốt