Question

Does an inverse exist for the following?


|-2 1|
|-6 1|

Answer 1

Use the simple trick for 2X2 matrices
\[\frac{ 1 }{ ad-bc }\ \left[\begin{matrix}-d & b \\ a & -c\end{matrix}\right]\]

Answer 2

an inverse exists if the determinant is not = 0

Answer 3

determinant being ad - bc

Answer 4

so the latex command for making a matrix is:

\left[\begin{matrix}-d & b \\ a & -c\end{matrix}\right]

good to know =D

ok so I got
\[\frac14\left[\begin{matrix}1 & -6 \\ 1 & -2\end{matrix}\right]\]
since that gives me a value.....It has an inverse!!!!!
Thanks guys!!!