\(\frac{5.4^{15}.9^9-4.3^{20}.8^9}{5.2^9.6^{19}-7.2^{29}.27^6}\)
\(=\frac{5.2^{30}.3^{18}-2^{29}.3^{20}}{5.2^{28}.3^{19}-7.2^{29}.3^{18}}\)
\(=\frac{2^{29}.3^{18}.\left(5.2-3^2\right)}{2^{28}.3^{18}.\left(5.3-7.2\right)}\)
\(=\frac{2^{29}.3^{18}.1}{2^{28}.3^{18}.1}\)
\(=2\)
\(\frac{5.4^{15}.9^9-4.3^{20}.8^9}{5.2^9.6^{19}-7.2^{29}.27^6}\)
\(=\frac{5.\left(2^2\right)^{15}.\left(3^2\right)^9-2^2.3^{20}.\left(2^3\right)^9}{5.2^9.2^{19}.3^{19}-7.2^{29}.\left(3^3\right)^6}\)
\(=\frac{5.2^{30}.3^{18}-2^2.3^{20}.2^{27}}{5.2^{28}.3^{19}-7.2^{29}.3^{18}}\)
\(=\frac{5.2^{29}.2.3^{18}-2^{29}.3^{18}.3^2}{5.2^{28}.3^{18}.3-7.2^{28}.2.3^{18}}\)
\(=\frac{2^{29}.3^{18}.\left(5.2-3^2\right)}{2^{28}.3^{18}.\left(5.3-7.2\right)}\)
\(=\frac{2^{29}.3^{18}.\left(10-9\right)}{2^{28}.3^{18}.\left(15-14\right)}\)
\(=\frac{2^{29}.3^{18}}{2^{28}.3^{18}}\)
\(=\frac{2^{28}.2.3^{18}}{2^{28}.3^{18}}\)
\(=2\)