Найти произведения матрицА×Ат и Ат×А: А=(1 2)(3 4)

Решите задачу:

$A = \left[\begin{array}{cc}1&2\\3&4\end{array}\right] ; At=\left[\begin{array}{cc}1&3\\2&4\end{array}\right]$
$A*At=\left[\begin{array}{cc}1&2\\3&4\end{array}\right] *\left[\begin{array}{cc}1&3\\2&4\end{array}\right] =\left[\begin{array}{cc}1*1+2*2&1*3+2*4\\3*1+4*2&3*3+4*4\end{array}\right] =$
$=\left[\begin{array}{cc}5&11\\11&25\end{array}\right]$
$At*A=\left[\begin{array}{cc}1&3\\2&4\end{array}\right] *\left[\begin{array}{cc}1&2\\3&4\end{array}\right] =\left[\begin{array}{cc}1*1+3*3&1*2+3*4\\2*1+4*3&2*2+4*4\end{array}\right] =$
$=\left[\begin{array}{cc}10&14\\14&20\end{array}\right]$