Tính A^3?
20/25
Cho \[{\rm{A}} = \left[ {\begin{array}{*{20}{c}}1&1\\0&1\end{array}} \right]\left[ {\begin{array}{*{20}{c}}2&0\\0&3\end{array}} \right]\left[ {\begin{array}{*{20}{c}}1&{ - 1}\\0&1\end{array}} \right]\]. Biết \[{\left[ {\begin{array}{*{20}{c}}{\rm{a}}&{\rm{0}}\\{\rm{0}}&{\rm{b}}\end{array}} \right]^{\rm{n}}}{\rm{ = }}\left[ {\begin{array}{*{20}{c}}{{{\rm{a}}^{\rm{n}}}}&{\rm{0}}\\{\rm{0}}&{{{\rm{b}}^{\rm{n}}}}\end{array}} \right]{\rm{(n}} \in {{\rm{N}}^{\rm{ + }}}{\rm{)}}\]. Tính A3?
\[\left[ {\begin{array}{*{20}{c}}{{2^3}}&0\\0&{{3^3}}\end{array}} \right]\]
\[\left[ {\begin{array}{*{20}{c}}{{2^3}}&{{3^3}}&{ - {2^3}}\\0&{{3^3}}&{}\end{array}} \right]\]
\[\left[ {\begin{array}{*{20}{c}}{{2^3}}&1\\0&{{3^3}}\end{array}} \right]\]
\[\left[ {\begin{array}{*{20}{c}}{{2^3}}&{{3^3}}&{ + {3^3}}\\0&{{3^3}}&{}\end{array}} \right]\]
Chọn đáp án D