a, \(139\frac{5}{7}:\frac{2}{3}−138\frac{2}{7}:\sqrt{\frac{4}{9}} \)

= \(139\frac{5}{7}:\frac{2}{3}−138\frac{2}{7}:\frac{2}{3}\)

= \((139\frac{5}{7}−138\frac{2}{7}):\frac{2}{3}\)

= \(1\frac{3}{7}:\frac{2}{3}\)

= \(2\frac{1}{7}\)

b, \((\frac{-5}{11}:\frac{13}{18}-\frac{5}{11}:\frac{13}{5})+\frac{-1}{33} \)

= \((\frac{5}{11}.\frac{-18}{13}-\frac{5}{11}.\frac{5}{13})+\frac{-1}{33}\)

= \([\frac{5}{11}.(\frac{-18}{13}-\frac{5}{13})]+\frac{-1}{33}\)

= \((\frac{5}{11}.\frac{-23}{13})+\frac{-1}{33}\)

= \(\frac{-155}{143}+\frac{-1}{33}\)

= \(\frac{-358}{429} \)

c, \(∣97\frac{2}{3}-125\frac{3}{5}∣+97\frac{2}{3}-125\frac{3}{5} \)

= \(∣\frac{-419}{15}∣+97\frac{2}{3}-125\frac{3}{5}\)

= \(\frac{419}{15}+97\frac{2}{3}-125\frac{3}{5}\)

= \(0\)

Tick cho mình nha!!!

Chúc bạn học tốt.

139\(\frac{5}{7}:\frac{2}{3}\)-\(138\frac{2}{7}:\sqrt{\frac{4}{9}}\)

=139\(\frac{5}{7}:\frac{2}{3}\)-\(138\frac{2}{7}:\frac{2}{3}\)

=\(\frac{2.2^9.3^9-2^5.2^4.3^8}{2.2^8.3^8}\)

=\(\frac{2^{10}.3^9-2^9.3^8}{2^9.3^8}\)

=\(\frac{2^9.3^8.\left(2.3-1\right)}{2^9.3^8}\)

=\(6-1\)

=5

\(\frac{-20+32\sqrt{7}}{9}\)

các bn trình bày bài giải cho mk nha :D

Mình làm như thế này nek

\(\frac{\frac{1}{4}+\frac{3}{7}-\frac{4}{5}}{0,75+\frac{9}{7}-2\frac{2}{5}}+\frac{\frac{3}{14}-\frac{2}{10}+\frac{5}{18}+\frac{7}{66}}{\frac{6}{7}-\frac{4}{5}+\frac{10}{9}+\frac{14}{33}}\)

\(=\frac{\frac{1}{4}+\frac{3}{7}-\frac{4}{5}}{\frac{2}{4}+\frac{9}{7}-\frac{12}{5}}+\frac{\frac{1}{2}\cdot\left(\frac{3}{7}-\frac{2}{5}+\frac{5}{9}+\frac{7}{33}\right)}{2\cdot\left(\frac{3}{7}-\frac{2}{5}+\frac{5}{9}+\frac{7}{33}\right)}\)

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

\(=\frac{1}{3}+\frac{1}{4}=\frac{7}{12}\)

\(\frac{\sqrt{7}-5}{2}-\frac{6-2\sqrt{7}}{4}+\frac{6}{\sqrt{7}-2}-\frac{5}{4+\sqrt{7}}\)

\(=\frac{\sqrt{7}-5}{2}-\frac{6+2\sqrt{7}}{4}+\frac{6\left(\sqrt{7}+2\right)}{\left(\sqrt{7}\right)^2-2^2}-\frac{5\left(4-\sqrt{7}\right)}{4^2-\left(\sqrt{7}\right)^2}\)

\(=\frac{\sqrt{7}-5}{2}-\frac{6+2\sqrt{7}}{4}+\frac{6\sqrt{7}+12}{3}-\frac{20-5\sqrt{7}}{8}\)

\(=\frac{12\left(\sqrt{7}-5\right)}{24}-\frac{6\left(6+2\sqrt{7}\right)}{24}+\frac{8\left(6\sqrt{7}+12\right)}{24}-\frac{3\left(20-5\sqrt{7}\right)}{24}\)

\(=\frac{12\sqrt{7}-60-36-12\sqrt{7}+48\sqrt{7}+96-60+15\sqrt{7}}{24}\)

\(=\frac{-60+63\sqrt{7}}{24}\)

Có  : \(5-\frac{5}{7-\frac{5}{7-\frac{5}{\frac{44}{7}}}}=5-\frac{5}{7-\frac{5}{7-5:\frac{44}{7}}}=5-\frac{5}{7-\frac{5}{7-\frac{35}{44}}}\)

     \(=5-\frac{5}{7-\frac{5}{\frac{273}{44}}}=5-\frac{5}{7-5:\frac{273}{44}}=5-\frac{5}{7-\frac{220}{273}}\)

       \(=5-\frac{5}{\frac{1691}{273}}=5-5:\frac{1691}{273}=5-\frac{1365}{1691}=\frac{7090}{1691}\)

         \(\Rightarrow\)Số nghịch đảo của biểu thức trên là \(\frac{1691}{7090}\)

 \(5-\frac{5}{7-\frac{5}{7-\frac{5}{7-\frac{5}{7}}}}\) \(\Rightarrow5-\frac{5}{7-\frac{5}{7-\frac{5}{\frac{44}{7}}}}=5-\frac{5}{7-\frac{5}{7-\frac{35}{44}}}=5-\frac{5}{7-\frac{5}{\frac{273}{44}}}=5-\frac{5}{7-\frac{220}{273}}\)

                             \(5-\frac{5}{\frac{1691}{273}}=5-\frac{1365}{1691}=\frac{7090}{1691}\)

a)  \(\frac{6}{5}.{\left( {1,2} \right)^8} = 1,2.{(1,2)^8} = {(1,2)^{1 + 8}} = {(1,2)^9}\)

b) \({\left( {\frac{{ - 4}}{9}} \right)^7}:\frac{{16}}{{81}} = {\left( {\frac{{ - 4}}{9}} \right)^7}:{\left( {\frac{{ - 4}}{9}} \right)^2} = {\left( {\frac{{ - 4}}{9}} \right)^{7 - 2}} = {\left( {\frac{{ - 4}}{9}} \right)^5}\)

\(C=9\cdot\left(\frac{\frac{26299}{2023}-\frac{3757}{2023}-\frac{91}{2023}}{\frac{8092}{2023}-\frac{1156}{2023}-\frac{28}{2023}}\right):\left(\frac{\frac{840255}{21545}+\frac{168051}{21545}+\frac{6045}{21545}+\frac{27105}{21545}}{\frac{344720}{21545}+\frac{68944}{21545}+\frac{2480}{21545}+\frac{11120}{21545}}\right)\cdot\frac{158158}{164164}\)

\(C=9\cdot\left(\frac{\frac{22451}{2023}}{\frac{6908}{2023}}\div\frac{\frac{1041456}{21545}}{\frac{427264}{21545}}\right)\cdot\frac{158158}{164164}\)

\(C=9\cdot\left(\frac{13}{4}\div\frac{39}{16}\right)\cdot\frac{158158}{164164}\)

\(C=9\cdot\frac{4}{3}\cdot\frac{2\cdot79\cdot2\cdot79}{2\cdot82\cdot2\cdot82}=9\cdot\frac{4}{3}\cdot\frac{79}{82}\)

\(C=\frac{474}{41}\)