Matrices

If \( A = \begin{bmatrix}1 & 2 \\ 3 & 4\end{bmatrix} \), what is the order of matrix \( A \)?

Which of the following matrices is a square matrix?

If \( A = \begin{bmatrix}1 & 2 \\ 3 & 4\end{bmatrix} \) and \( B = \begin{bmatrix}2 & 0 \\ 1 & 2\end{bmatrix} \), find \( A + B \).

If \( A = \begin{bmatrix}2 & -1 \\ 0 & 3\end{bmatrix} \), what is \( 3A \)?

If \( A = \begin{bmatrix}1 & 2 \\ 3 & 4\end{bmatrix} \) and \( B = \begin{bmatrix}0 & 1 \\ 2 & 3\end{bmatrix} \), find \( AB \).

For matrix \( A = \begin{bmatrix}a & b \\ c & d\end{bmatrix} \), the determinant is given by:

If \( A = \begin{bmatrix}4 & 7 \\ 2 & 6\end{bmatrix} \), find \( A^{-1} \).

If \( A \) is a \( 2 \times 2 \) matrix such that \( A^2 = I \) (identity matrix), which of the following is always true?

If \( A = \begin{bmatrix}1 & 2 & 3 \\ 0 & 1 & 4\end{bmatrix} \) and \( B = \begin{bmatrix}2 & 0 \\ 1 & 3 \\ 0 & 4\end{bmatrix} \), find the order of the product \( AB \).