Giải:
\(B=\dfrac{\left(\dfrac{2}{3}\right)^3.\left(-\dfrac{3}{4}\right)^2.\left(-1\right)^{2003}}{\left(\dfrac{2}{5}\right)^2.\left(-\dfrac{5}{12}\right)^3}\)
\(\Leftrightarrow B=\dfrac{\left(\dfrac{2}{3}\right)^3.\left(\dfrac{3}{4}\right)^2.\left(-1\right)}{\left(\dfrac{2}{5}\right)^2.\left(-\dfrac{5}{12}\right)^3}\)
\(\Leftrightarrow B=\dfrac{\left(\dfrac{2}{3}\right)^3.\left(\dfrac{3}{4}\right)^2}{\left(\dfrac{2}{5}\right)^2.\left(\dfrac{5}{12}\right)^3}\)
\(\Leftrightarrow B=\dfrac{\dfrac{2^3.3^2}{3^3.4^2}}{\dfrac{2^2.5^3}{5^2.12^3}}\)
\(\Leftrightarrow B=\dfrac{2^3.3^2.5^2.12^3}{3^3.4^2.2^2.5^3}\)
\(\Leftrightarrow B=\dfrac{2^3.3^2.5^2.2^6.3^3}{3^3.2^4.2^2.5^3}\)
\(\Leftrightarrow B=\dfrac{2^9.3^5.5^2}{3^3.2^6.5^3}\)
\(\Leftrightarrow B=\dfrac{2^3.3^2}{5}\)
\(\Leftrightarrow B=\dfrac{72}{5}\)
Vậy ...
\(B=\dfrac{\left(\dfrac{2}{3}\right)^3.\left(-\dfrac{3}{4}\right)^2.\left(-1\right)^{2003}}{\left(\dfrac{2}{5}\right)^2.\left(-\dfrac{5}{12}\right)^3}=\dfrac{\dfrac{8}{27}.\dfrac{9}{16}.\left(-1\right)}{\dfrac{4}{25}.\left(-\dfrac{125}{1728}\right)}=\dfrac{\dfrac{-1}{6}}{\dfrac{-5}{432}}=\dfrac{72}{5}\)
