chịu

\(=\dfrac{2^{12}\cdot3^{10}+2^{12}\cdot3^{10}\cdot5}{2^{12}\cdot3^{12}+2^{11}\cdot3^{11}}=\dfrac{2^{13}\cdot3^{11}}{2^{11}\cdot3^{11}\cdot7}=\dfrac{4}{7}\)

\(\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}=\frac{\left(2^2\right)^6.\left(3^2\right)^5+\left(2.3\right)^9.2^3.3.5}{\left(2^3\right)^4.3^{12}-\left(2.3\right)^{11}}\)

                                \(=\frac{2^{12}.3^{10}+2^{12}.3^{10}.5}{2^{12}.3^{12}-2^{11}.3^{11}}\)

                                \(=\frac{2^{12}.3^{10}}{2^{11}.3^{11}}.\frac{1+5}{2.3-1}\)

                                \(=\frac{2^{12}.3^{10}}{2^{11}.3^{11}}.\frac{6}{5}\)

                                \(=\frac{2}{3}.\frac{6}{5}\)

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

Bài này trong sgk

\(=\frac{\left(2^2\right)^6.\left(3^2\right)^5+\left(2.3\right)^9.8.3.5}{\left(2^3\right)^4.3^{12}+\left(2.3+1\right)}=\frac{2^{12}.3^{10}+2^9.3^9.2^3.3.5}{2^{12}.3^{12}+2^{11}.3^{11}}=\frac{2^{12}.3^{10}.\left(1+5\right)}{2^{11}.3^{11}.\left(2.3+1\right)} \)

\(\frac{2.3.6}{7}=\frac{36}{7}\)

Mình ghi mỏi tay 

\(\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}\)= \(\frac{4096.59049+10077696.120}{4096.531441-362797056}\)= \(\frac{241864704+1209323520}{2176782336-362797056}\)= \(\frac{1451188224}{1813985280}\)

\(\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}=\frac{4}{5}\)

4/5 nha bạn 

Chúc bạn học tốt !!

\(A=\frac{4^6\cdot9^5+6^9\cdot120}{8^4\cdot3^{12}-6^{11}}=\frac{\left(2^2\right)^6\cdot\left(3^2\right)^5+\left(2\cdot3\right)^9\cdot2^3\cdot3\cdot5}{\left(2^3\right)^4\cdot3^{12}-\left(2\cdot3\right)^{11}}=\frac{2^{12}\cdot3^{10}+2^9\cdot3^9\cdot2^3\cdot3\cdot5}{2^{12}\cdot3^{12}-2^{11}\cdot3^{11}}=\frac{2^{12}\cdot3^{10}+2^{12}\cdot3^{10}\cdot5}{2^{12}\cdot3^{12}-2^{11}\cdot3^{11}}=\frac{2^{12}\cdot3^{10}\left(1+5\right)}{2^{11}\cdot3^{11}\left(2\cdot3-1\right)}=\frac{2\left(1+5\right)}{3\left(6-1\right)}=\frac{2\cdot6}{3\cdot5}=\frac{2\cdot2}{5}=\frac{4}{5}\)

                                                             \(\approx GOOD\)\(LUCK\approx\)

Đáp án ở đây

https://giaibaitapvenha.blogspot.com/

\(A=\)\(\frac{4^6.9^5+6^9.120}{6^{11}+8^4.3^{12}}\)

\(A=\frac{2^{12}.3^{10}+6^9.6.2^2.5}{6^{11}+2^{12}.3^{12}}\)

\(A=\frac{2^{12}.3^{10}+6^{10}.2^2.5}{6^{11}+2^{12}.3^{12}}\)

\(A=\frac{2^{12}.3^{10}+2^{10}.3^{10}.2^2.5}{\left(2.3\right)^{11}+2^{12}.3^{12}}\)

\(A=\frac{2^{12}.3^{10}+2^{12}.3^{10}.5}{2^{11}.3^{11}+2^{12}.3^{12}}\)

\(A=\frac{2^{12}.3^{10}.\left(1+5\right)}{2^{11}.3^{11}.\left(1+2.3\right)}\)

\(A=\frac{2^{12}.3^{10}.6}{2^{11}.3^{11}.7}\)

\(A=\frac{2^{12}.3^{10}.2.3}{2^{11}.3^{11}.7}\)

\(A=\frac{2^{13}.3^{11}}{2^{11}.3^{11}.7}\)

\(A=\frac{2^2}{7}\)\(=\frac{4}{7}\)