Đáp án:
$\dfrac{1}{2^{31}. 3^{33}}$
Giải thích các bước giải:
$\dfrac{12^{19}.9^4}{6^{60}.8^3}$ = $\dfrac{(3.2^2)^{19}.(3^2)^4}{(2.3)^{60}.(2^3)^3}$
= $\dfrac{3^{19}.2^{38}.3^8}{2^{60}.3^{60}.2^9}$
= $\dfrac{3^{27}.2^{38}}{2^{69}.3^{60}}$
= $\dfrac{1}{2^{31}. 3^{33}}$