Inverse of a matrix

Question

Derive the inverse matrix A−1 when A =[30&12 10&4]

Answer 1

For a 2 by 2 matrix, the inverse can be done by first computing the matrix's determinant.

Assuming that you have supplied top row 30 & 12, bottom row 10 & 4, this determinant is 0.

There is no inverse for this particular square matrix.

 

A matrix MAY only have an inverse if it's square, but that is not a sufficient condition.

 

Even if your data had been given in columnar fashion, this determinant is still zero.