Đáp án:
\(A = \frac{1}{8}\)
Giải thích các bước giải:
\(\begin{array}{l}
A = \frac{{{{5.4}^{15}}{{.9}^9} - {{4.3}^{20}}{{.8}^9}}}{{{{5.2}^{10}}{{.6}^{19}} - {{7.2}^{29}}{{.27}^6}}}\\
= \frac{{{{5.2}^{30}}{{.3}^{18}} - {3^{20}}{{.2}^{29}}}}{{{{5.3}^{19}}{{.2}^{29}} - {{7.2}^{29}}{{.3}^{18}}}}\\
= \frac{{{2^{29}}{{.3}^{18}}\left( {5.2 - 9} \right)}}{{{2^{29}}{{.3}^{18}}.\left( {5.3 - 7} \right)}} = \frac{1}{8}
\end{array}\)