# Thread: Matrices and complex numbers

1. ## Matrices and complex numbers

Hi,

$C = \left(\begin{array}{ccc}s&3&4\\1+s&1-s&2\\0&-1&1\end{array}\right)$

For which two complex values of s is C singular?

a) What is meant by the term singular? Is it just ones across the matrix or something else entirely?

b) How do I begin to work it out, what steps should I take?

EDIT: I understand it now but thanks to anyone who attempted it for me

2. A matrix is singular if and only if its determinate equals 0.

Ya know how to find the determinate of a 3x3 matrix?