Resposta e explicação passo a passo:
[tex]\left[\begin{array}{ccc}1&3\\-1&-4\end{array}\right]-\left[\begin{array}{ccc}4&3\\-1&-1\end{array}\right]=\left[\begin{array}{ccc}1-4&3-3\\-1-(-1)&-4-(-1)\end{array}\right]=\left[\begin{array}{ccc}-3&0\\0&-3\end{array}\right][/tex]
