\(\frac{5.4^{15}.9^8-4.3^{17}.8^9}{5.2^{11}.6^{18}-7.2^{28}.27^6}\)\(=\frac{5.\left(2^2\right)^{15}.\left(3^2\right)^8-\left(2^2\right).3^{17}.\left(2^3\right)^9}{5.2^{11}.\left(2.3\right)^{18}-7.2^{28}.\left(3^3\right)^6}\)\(=\frac{5.2^{30}.3^{16}-2^2.3^{17}.2^{27}}{5.2^{11}.2^{18}.3^{18}-7.2^{28}.3^{18}}\)
\(=\frac{5.2^{30}.3^{16}-2^{29}.3^{17}}{5.2^{29}.3^{18}-7.2^{28}.3^{18}}=\frac{2^{28}.3^{16}.\left(5.2^2-2.3\right)}{2^{28}.3^{16}.\left(5.2.3^2-7.3^2\right)}\)
\(=\frac{5.2^2-2.3}{5.2.3^2-7.3^2}=\frac{5.4-6}{5.2.9-7.9}=\frac{20-6}{90-63}\)
\(=\frac{14}{27}\)
\(\frac{5.4^{15}.9^8-4.3^{17}.8^9}{5.2^{11}.6^{18}-7.2^{28}.27^6}=\frac{5.\left(2^2\right)^{15}.\left(3^2\right)^8-2^2.3^{17}.\left(2^3\right)^9}{5.2^{11}.\left(2.3\right)^{18}-7.2^{28}.\left(3^3\right)^6}\)\(=\frac{5.2^{30}.3^{16}-2^2.3^{17}.2^{27}}{5.2^{11}.2^{18}.3^{18}-7.2^{28}.3^{18}}=\frac{5.2^{30}.3^{16}-2^{29}.3^{17}}{5.2^{29}.3^{18}-7.2^{28}.3^{18}}\)\(=\frac{2^{29}.3^{16}.\left(5+2-3\right)}{2^{28}.3^{18}.\left(5+2\right)}\)\(=\frac{2.4}{3^2.7}=\frac{8}{63}\)
thế nếu phần tử mà là:.5.4^15.9^8-4-3^13.8^9(giữ nguyên mau) thì sao
