Find the Inverse [[4,8],[2,4]]

$[\begin{array}{c} 4 & 8 \\ 2 & 4 \end{array}]$

Step 1

Find the determinant.

The determinant of a $2 \times 2$ matrix can be found using the formula $| \begin{array}{c} a & b \\ c & d \end{array} | = a d - c b$ .

$4 \cdot 4 - 2 \cdot 8$

Simplify the determinant.

Simplify each term.

Multiply $4$ by $4$ .

$16 - 2 \cdot 8$

Multiply $- 2$ by $8$ .

$16 - 16$

Subtract $16$ from $16$ .

$0$

Step 2

There is no inverse because the determinant is $0$ .