Question

what is the cofactor expansion of 2*2 matrix

Answer 1

@abstracted

Answer 2

So the cofactor expansion of any matrix is a method for determining the determinate of the matrix.

If you have the matrix
\[\left[\begin{matrix}a & b \\ c & d\end{matrix}\right]\]

The determinate is\[ad-bc\]

Answer 3

For determinates larger than 3x3, by use of cofactor expansion, look at this

http://comp.uark.edu/~jjrencis/femur/Learning-Modules/Linear-Algebra/solving/determinant/cofactor_expansion.html

Answer 4

thanks ....atleast u had tried ... but i was looking for a cofactor expansion not a determinant.....

Answer 5

A cofactor expansion is the exact same as the determinate.

If you have the matrix
\[\left[\begin{matrix}a & b \\ c & d\end{matrix}\right]\]

Both the cofactor expansion and the determinate is:
\[ad-bc\]

Answer 6

i got it from that link u share .... thanks..@abstracted