Có \(\hept{\begin{cases}A=\frac{-9}{10^{2012}}+\frac{-19}{10^{2011}}\\B=\frac{-19}{10^{2012}}+\frac{-9}{10^{2011}}\end{cases}}\)
\(\Rightarrow\)A-B=\(\frac{10}{10^{2011}}-\frac{10}{10^{2012}}=\frac{1}{10^{2010}}-\frac{1}{10^{2011}}>0\)
\(\Rightarrow A>B\)