Đáp án:
\[\frac{{8{a^3}}}{{2a - b}}\]
Giải thích các bước giải:
Ta có:
\(\begin{array}{l}
\frac{{8{a^3}\left( {4{a^2} - {b^2}} \right)}}{{\left( {2a + b} \right)\left( {4{a^2} - 4ab + {b^2}} \right)}}\\
= \frac{{8{a^3}\left[ {{{\left( {2a} \right)}^2} - {b^2}} \right]}}{{\left( {2a + b} \right)\left[ {{{\left( {2a} \right)}^2} - 2.2a.b + {b^2}} \right]}}\\
= \frac{{8{a^3}\left( {2a - b} \right)\left( {2a + b} \right)}}{{\left( {2a + b} \right){{\left( {2a - b} \right)}^2}}} = \frac{{8{a^3}}}{{2a - b}}
\end{array}\)