In a compact single dimensional array representation for lower triangular matrices (i.e., all the elements above the diagonal are zero) of size $$n$$ $$x$$ $$n$$, non-zero elements (i.e., elements of the lower triangle) of each row are stored one after another, starting from the first row, the index of the $${\left( {i,\,j} \right)^{th}}$$ element of the lower triangular matrix in this new representation is

A square matrix is singular whenever:

If a, b and c are constants, which of the following is a linear inequality?