a.

\(\frac{45^{10}\times5^{20}}{75^{15}}=\frac{\left(3^2\times5\right)^{10}\times5^{20}}{\left(3\times5^2\right)^{15}}=\frac{3^{20}\times5^{10}\times5^{20}}{3^{15}\times5^{30}}=3^5=243\)

b.

\(\frac{\left(0,8\right)^5}{\left(0,4\right)^6}=\frac{\left(0,8\right)^5}{\left(0,4\right)^5}\times\frac{1}{\left(0,4\right)}=\left(\frac{0,8}{0,4}\right)^5\times\frac{1}{\frac{4}{10}}=2^5\times\frac{5}{2}=2^4\times5=16\times5=80\)

c.

\(\frac{2^{15}\times9^4}{6^6\times8^3}=\frac{2^{15}\times\left(3^2\right)^4}{\left(2\times3\right)^6\times\left(2^3\right)^3}=\frac{2^{15}\times3^8}{2^6\times3^6\times2^9}=3^2=9\)

Chúc bạn học tốt ^^

a) A = \(\frac{45^{10}.5^{10}}{75^{10}}=\frac{\left(5.3^2\right)^{10}.5^{10}}{\left(5^2.3\right)^{10}}=\frac{5^{10}.3^{20}.5^{10}}{5^{20}.3^{10}}=\frac{5^{20}.3^{10}}{5^{20}}=3^{10}=59049\)

b) B = \(\frac{\left(0,8\right)^5}{\left(0,4\right)^6}=\frac{\left(0,2.2^2\right)^5}{\left(0,2.2\right)^6}=\frac{\left(0,2\right)^5.2^{10}}{\left(0,2\right)^6.2^6}=\frac{2^4}{0,2}=\frac{16}{0,2}=80\)

c) C = \(\frac{2^{15}.9^4}{6^6.8^3}=\frac{2^{15}.\left(3^2\right)^4}{\left(2.3\right)^6.\left(2^3\right)^3}=\frac{2^{15}.3^8}{2^6.3^6.2^9}=\frac{2^{15}.3^2}{2^{15}}=3^2=9\)

\(A=\frac{\left(9^{10}×5^{10}×5^{10}\right)}{\left(25^{10}×3^{10}\right)}\)

\(A=\frac{\left(3^{20}×5^{20}\right)}{\left(5^{20}×3^{10}\right)}\)

\(A=\frac{3^{20}}{3^{10}}\)

\(A=3^{10}\)

\(\frac{\left(0,8^5\right)}{\left(0,4^6\right)}=80\)

nha bạn 

\(\frac{\left(0,8^5\right)}{\left(0,4^6\right)}=80\)nha  Linh Nguyễn                               ^_^

\(\frac{0,8^5}{0,4^6}=\frac{\frac{1024}{3125}}{\frac{64}{16525}}=80\)

\(P=\left(\dfrac{-1}{2}-\dfrac{3}{5}\right):\left(-3\right)+\dfrac{1}{3}-\dfrac{1}{6}:2\)

\(=\left(\dfrac{1}{2}+\dfrac{3}{5}\right):3+\dfrac{1}{3}-\dfrac{1}{12}\)

\(=\dfrac{11}{10}\cdot\dfrac{1}{3}+\dfrac{1}{4}\)

\(=\dfrac{11}{30}+\dfrac{1}{4}=\dfrac{22}{60}+\dfrac{15}{60}=\dfrac{37}{60}\)

\(Q=\left(\dfrac{2}{25}-\dfrac{126}{125}\right)\cdot\dfrac{7}{4}:\left[\dfrac{-119}{36}\cdot\dfrac{36}{17}\right]\)

\(=\dfrac{-116}{125}\cdot\dfrac{7}{4}:\left(-7\right)\)

\(=\dfrac{116}{125}\cdot\dfrac{7}{4}\cdot\dfrac{1}{7}=\dfrac{29}{125}\)

\(M=\left(\dfrac{1}{3}\right)^{12}\cdot\left(\dfrac{1}{3}\right)^{-15}+\left(\dfrac{2}{5}\right)^{-4}\cdot5^{-4}\cdot32\)

\(=\left(\dfrac{1}{3}\right)^{-3}+2^{-4}\cdot32\)

\(=27+\dfrac{32}{16}=27+2=29\)

\(=\left(\dfrac{0,8}{0,4}\right)^5\cdot\dfrac{1}{0,4}=2^5\cdot\dfrac{1}{0,4}=\dfrac{32}{0,4}=80\)

Giải:

\(\dfrac{\left(0,8\right)^5}{\left(0,4\right)^6}\)

= \(\left(\dfrac{0,8}{0,4}\right)^5.\dfrac{1}{0,4}\)

= \(2^5.\dfrac{1}{0,4}\)

= \(\dfrac{32}{0,4}=80\)

Hok tốt 

Tính giá trị biểu thức

\(\dfrac{2^{15}.9^4}{6^3.8^3}\)

Giups mik vs

\(\begin{array}{l}a)\left( {\frac{2}{3} + \frac{1}{6}} \right):\frac{5}{4} + \left( {\frac{1}{4} + \frac{3}{8}} \right):\frac{5}{2}\\ = \left( {\frac{4}{6} + \frac{1}{6}} \right).\frac{4}{5} + \left( {\frac{2}{8} + \frac{3}{8}} \right).\frac{2}{5}\\ = \frac{5}{6}.\frac{4}{5} + \frac{5}{8}.\frac{2}{5}\\ = \frac{2}{3} + \frac{1}{4}\\ = \frac{8}{{12}} + \frac{3}{{12}}\\ = \frac{{11}}{{12}}\\b)\frac{5}{9}:\left( {\frac{1}{{11}} - \frac{5}{{22}}} \right) + \frac{7}{4}.\left( {\frac{1}{{14}} - \frac{2}{7}} \right)\\ = \frac{5}{9}:\left( {\frac{2}{{22}} - \frac{5}{{22}}} \right) + \frac{7}{4}.\left( {\frac{1}{{14}} - \frac{4}{{14}}} \right)\\ = \frac{5}{9}:\frac{{ - 3}}{{22}} + \frac{7}{4}.\frac{{ - 3}}{{14}}\\ = \frac{5}{9}.\frac{{ - 22}}{3} + \frac{{ - 3}}{8}\\ = \frac{{ - 110}}{{27}} + \frac{{ - 3}}{8}\\ = \frac{{ - 880}}{{216}} + \frac{{ - 81}}{{216}}\\ = \frac{{ - 961}}{{216}}\end{array}\)