Question

Am nevoie de ajutor,este urgent!!!,in clasa nu am facut exemple ca in fisa,dau coroana!!​

Answer 1

$\it 1.\ a)\\ \\ A+I_2=\begin{pmatrix}2&1\\3&4\end{pmatrix};\ \ \begin{vmatrix}2&1\\3&4\end{vmatrix}=4\cdot2-3\cdot1=5\\ \\ \\ b)\ \ A\cdot A=\begin{pmatrix}1&1\\3&3\end{pmatrix}\cdot \begin{pmatrix}1&1\\3&3\end{pmatrix}=\begin{pmatrix}4&4\\12&12\end{pmatrix}=4\cdot \begin{pmatrix}1&1\\3&3\end{pmatrix}=4A$