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 ^^

cảm ơn bạn

I don't now 

sorry 

...................

nha

\(A=\frac{2^{15}.9^4}{6^6.8^3}=\frac{2^{15}.3^8}{2^6.3^6.2^9}=\frac{2^{15}.3^2}{3^{15}}=9\)

\(B=\frac{45^{10}.5^{10}}{75^{10}}=\frac{5^{10}.3^{20}.5^{10}}{5^{20}.3^{10}}=3^{10}\)

\(C=\frac{\left(0,8\right)^5}{\left(0,4\right)^6}=\frac{\left(0,4\right)^5.\left(0,2\right)^5}{0,4^6}=\frac{0,2^5}{0,2^2}=0,2^3\)

\(D=\frac{8^{10}+4^{10}}{8^{11}+4^{11}}=\frac{4^{10}\left(2^{10}+1\right)}{4^{11}\left(2^{11}+1\right)}=\frac{2^{10}+1}{2^{13}+1}\)

1. sai dấu nhé 

2.a, \(\frac{45^{10}.5^{20}}{75^{15}}=\frac{\left(3^2.5\right)^{10}.5^{20}}{\left(5^2.3\right)^{15}}=\frac{3^{20}.5^{30}}{5^{30}.3^{15}}=3^5=243\)

b, \(\frac{\left(0,8\right)^5}{\left(0,4\right)^6}=\frac{\left(\frac{4}{5}\right)^5}{\left(\frac{2}{5}\right)^6}=\frac{\left(\frac{2}{5}\cdot2\right)^5}{\left(\frac{2}{5}\right)^6}=\frac{\left(\frac{2}{5}\right)^5\cdot2^5}{\left(\frac{2}{5}\right)^5\cdot\frac{2}{5}}=2^5\div\frac{2}{5}=32\cdot\frac{5}{2}=80\)

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

a) \(\frac{45^{10}.5^{20}}{75^{15}}=\frac{\left(3^2.5\right)^{10}.5^{20}}{\left(3.5^2\right)^{15}}=\frac{3^{20}.5^{10}5^{20}}{3^{15}.5^{30}}=\frac{3^{20}.5^{30}}{3^{15}.5^{30}}=3^5=243\)

b) \(\frac{\left(0,8\right)^5}{\left(0,4\right)^6}=\left(0,8\right)^5:\left(0,4\right)^6=\left(\frac{4}{5}\right)^5:\left(\frac{2}{5}\right)^6=\frac{4^5}{5^5}:\frac{2^6}{5^6}=\frac{4^5}{5^5}.\frac{5^6}{2^6}=\frac{2^{10}}{5^5}.\frac{5^6}{2^6}=2^4.5=16.5=80\)

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

b)\(\frac{\left(0,8\right)^5}{\left(0,4\right)^6}=\frac{\left(2.0,4\right)^5}{\left(0,4\right)^6}=\frac{2^5.\left(0,4\right)^5}{\left(0,4\right)^6}=\frac{2^5}{0,4}=\frac{2^5}{\frac{2}{5}}=\frac{2^4}{5}=\frac{16}{5}\)

c)\(\frac{2^{15}.9^4}{6^6.8^3}=\frac{2^{15}.3^{12}}{3^6.2^6.2^9}=3^6\)

a)\(\frac{45^{10}.5^{20}}{75^{15}}=\frac{15^{10}.3^{10}.5^{20}}{5^{15}.15^{15}}=\frac{3^{10}.5^5}{15^5}=\frac{3^{10}.5^5}{5^5.3^5}=3^5\)

Thanks bn!!

Câu 1:\(\frac{45^{10}.5^{10}}{75^{10}}\) = \(\frac{\left(5.9\right)^{10}.5^{10}}{\left(5.5.3\right)^{10}}\) = \(\frac{5^{10}.9^{10}.5^{10}}{5^{10}.5^{10}.3^{10}}\) = \(\frac{9^{10}}{3^{10}}\) = \(\frac{3^{10}.3^{10}}{3^{10}}\) = \(3^{10}\) = 59049

Câu 2:\(\frac{\left(0,8\right)^5}{\left(0,4\right)^6}\) = \(\frac{\left(0,4.2\right)^5}{\left(0,4\right)^6}\) = \(\frac{\left(0,4\right)^5.2^5}{\left(0,4\right)^6}\) = \(\frac{2^5}{0,4}\) = \(\frac{32}{0,4}\) = 80

Câu 3:\(\frac{2^{15}.9^4}{6^3.8^3}\) = \(\frac{2^{15}.3^8}{2^{12}.3^3}\) = \(\frac{2^3.3^5}{1.1}\) = \(\frac{8.243}{1}\) = 1944

Câu 4: \(\frac{8^{10}+4^{10}}{8^4+4^{11}}\) = \(\frac{\left(2^3\right)^{10}+\left(2^2\right)^{10}}{\left(2^3\right)^4+\left(2^2\right)^{11}}\) = \(\frac{2^{30}+2^{20}}{2^{12}+2^{22}}\) = \(\frac{2^{20}.2^{10}+2^{20}}{2^{12}+2^{12}.2^{10}}\) = \(\frac{2^{20}\left(2^{10}+1\right)}{2^{12}\left(2^{10}+1\right)}\) = \(\frac{2^{20}}{2^{12}}\) = \(\frac{2^8}{1}\) = \(2^8\) = 256