Find AAT
Given:
\[ A = \begin{bmatrix} 1 & 2 & 3 \end{bmatrix} \]
Step 1: Find AT
\[ A^T = \begin{bmatrix} 1 \\ 2 \\ 3 \end{bmatrix} \]
Step 2: Multiply AAT
\[ AA^T = \begin{bmatrix} 1 & 2 & 3 \end{bmatrix} \begin{bmatrix} 1 \\ 2 \\ 3 \end{bmatrix} \]
\[ AA^T = 1^2 + 2^2 + 3^2 = 1 + 4 + 9 = 14 \]
Final Answer:
\[ AA^T = \begin{bmatrix} 14 \end{bmatrix} \]