Question

For what value of k, the matrix a=[2-k 3 -5 1] is not invertible.

Answer 1

Answer:

A Square matrix is said to be Invertible if it's inverse exists, and is said to be non Invertible if it's determinant is equal to Zero.

A non invertible matrix is also called singular matrix.

$\begin{vmatrix}2-k & 3 \\ -5 & 1\end{vmatrix}=0\\\\ 2-k+3\times(-5)=0\\\\2-15=k\\\\k=-13$

Answer 2

Answer:

k is not equal to zero

(2- k) -3 (-5) not equal 0

k= -13