\(=\frac{16}{5}.\frac{15}{16}-\left(\frac{3}{4}+\frac{2}{7}\right):\left(\frac{-29}{28}\right)\)

\(=3-\left(\frac{21}{28}+\frac{8}{28}\right):\left(\frac{-29}{28}\right)\)

\(=3-\left(\frac{29}{28}\right).\left(\frac{-28}{29}\right)\)

\(=3-\left(-1\right)\)

\(=4\)

b)   \(=\left(\frac{1}{4}+\frac{25}{2}-\frac{5}{16}\right):\left(12-\frac{7}{12}:\left(\frac{3}{8}-\frac{1}{12}\right)\right)\)

       \(=\left(\frac{4}{16}+\frac{200}{16}-\frac{5}{16}\right):\left(12-\frac{7}{12}:\left(\frac{3.3}{2.3.4}-\frac{2}{2.3.4}\right)\right)\)

     \(=\left(\frac{199}{16}\right):\left(12-\frac{7}{12}:\left(\frac{9}{24}-\frac{2}{24}\right)\right)\)

      \(=\frac{199}{16}:\left(12-\frac{7}{12}.\frac{24}{7}\right)\)

    \(=\frac{199}{16}:\left(12-2\right)\)

\(=\frac{199}{16}:10\)

\(=\frac{199}{160}\)

c)   \(\left(\frac{-3}{5}+\frac{5}{11}\right):\frac{-3}{7}+\left(\frac{-2}{5}+\frac{6}{5}\right):\frac{-3}{7}\)

\(\left(\frac{-33}{55}+\frac{25}{55}\right):\frac{-3}{7}+\left(\frac{4}{5}\right):\frac{-3}{7}\)

\(\left(\frac{-8}{55}\right).\frac{-7}{3}+\frac{4}{5}.\frac{-7}{3}\)

\(\frac{-7}{3}\left(\frac{-8}{55}+\frac{4}{5}\right)\)

\(\frac{-7}{3}.\frac{36}{55}=\frac{-84}{55}\)

giờ mk phải đi ngủ r mai mk làm cho 

gaegaegd

3,

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

= \(-\frac{5}{21}:\frac{4}{5}+\frac{5}{21}:\frac{4}{5}\)

= \(\left(-\frac{5}{21}+\frac{5}{21}\right):\frac{4}{5}\)

= \(0:\frac{4}{5}=0\)

2,

a) \(\frac{-3}{4}\))

= \(\frac{-3.4.3.\left(-5\right).5}{4.\left(-5\right).3.3}\)

= \(-5\)

b) ().\(\frac{-38}{21}\)

= \(\frac{19}{8}\)

c)

= \(\left(\frac{11}{12}.\frac{16}{33}\right).\frac{3}{5}\)

= \(\frac{4}{9}.\frac{3}{5}\)

= \(\frac{4}{15}\)

d) \(\frac{7}{23}\left[\left(\frac{-8}{6}\right)-\frac{45}{18}\right]\)

= \(\frac{7}{23}.\left(\frac{-41}{10}\right)\)

= \(\frac{-287}{203}\)

3. Tính:

a)

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

= 0 : \(\frac{4}{5}\)

= 0

b) \(\frac{5}{9}\)\(\frac{5}{9}\)

: \(\frac{-3}{22}\)+ \(\frac{5}{9}\): \(\frac{-3}{5}\)

= \(\frac{5}{9}\): \(\frac{-81}{110}\)

= \(\frac{-550}{729}\)

a: \(\Leftrightarrow\dfrac{1}{2}-\dfrac{7}{12}< x< \dfrac{1}{48}+\dfrac{5}{48}=\dfrac{6}{48}=\dfrac{1}{8}\)

\(\Leftrightarrow-\dfrac{1}{12}< x< \dfrac{1}{8}\)

=>x=0

c: \(\Leftrightarrow x=\dfrac{-1}{2}\cdot\dfrac{1}{4}=\dfrac{-1}{8}\)

d: \(\Leftrightarrow x^8=x^7\)

=>x(x-1)=0

=>x=0(loại) hoặc x=1(nhận)

e: \(\Leftrightarrow3^x=\dfrac{3^{10}}{3^9}=3\)

hay x=1

f: =>x-1=20

hay x=21

\(12\frac{3}{11}-\frac{6}{13}+3,25-5\frac{3}{11}+\sqrt{1\frac{9}{16}}\)

\(=\frac{135}{11}-\frac{6}{13}+\frac{13}{4}-\frac{58}{11}+\sqrt{\frac{25}{16}}\)

\(=\frac{135}{11}-\frac{6}{13}+\frac{13}{4}-\frac{58}{11}+\frac{5}{4}\)

\(=\frac{135}{11}-\frac{58}{11}+\frac{13}{4}+\frac{5}{4}-\frac{6}{13}\)

\(=\frac{77}{11}+\frac{18}{4}-\frac{6}{13}\)

\(=7+\frac{9}{2}-\frac{6}{13}\)

\(=\frac{182}{26}+\frac{117}{26}-\frac{12}{26}\)

\(=\frac{287}{26}\)

Tính:

a) \(-3\frac{3}{4}+\left(-\frac{10}{25}\right)+\left(-\frac{6}{12}\right)\)

\(=\left(-\frac{15}{4}\right)+\left(-\frac{10}{25}\right)+\left(-\frac{6}{12}\right)\)

\(=\left(-\frac{83}{20}\right)+\left(-\frac{6}{12}\right)\)

\(=-\frac{93}{20}.\)

b) \(-0,6-\left(-\frac{4}{9}\right)-\frac{16}{15}\)

\(=\left(-\frac{3}{5}\right)-\left(-\frac{4}{9}\right)-\frac{16}{15}\)

\(=\left(-\frac{7}{45}\right)-\frac{16}{15}\)

\(=-\frac{11}{9}.\)

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