Đáp án: $\frac{7}{2}$
Giải thích các bước giải:
$\eqalign{ & \frac{{{{( - 6)}^{12}}{{.49}^7}}}{{{{14}^{13}}{{.9}^6}}} \cr & = \frac{{{6^{12}}.{{({7^2})}^7}}}{{{{(2.7)}^{13}}.{{({3^2})}^6}}} \cr & = \frac{{{{(2.3)}^{12}}{{.7}^{14}}}}{{{2^{13}}{{.7}^{13}}{{.3}^{12}}}} \cr & = \frac{{{2^{12}}{{.3}^{12}}{{.7}^{14}}}}{{{2^{13}}{{.3}^{12}}{{.7}^{13}}}} \cr & = \frac{7}{{2}} \cr} $