# How do you find the determinant of ((1, 2), (1, 3))?

Oct 31, 2016

$| \left(1 , 2\right) , \left(1 , 3\right) | = 1$

#### Explanation:

If we have a matrix $A = \left(\begin{matrix}a & b \\ c & d\end{matrix}\right)$, then the determinant of $A$ denoted $\det \left(A\right)$ or $| A |$ is calculated as:
$| A | = \det \left(A\right) = a \cdot d - b \cdot c$

$\therefore | \left(1 , 2\right) , \left(1 , 3\right) | = \left(1\right) \left(3\right) - \left(2\right) \left(1\right)$
$\therefore | \left(1 , 2\right) , \left(1 , 3\right) | = 3 - 2$
$\therefore | \left(1 , 2\right) , \left(1 , 3\right) | = 1$