A generic drug is the same as a brand-name drug in dosage, safety, strength, quality, the way it works, the way it is taken and the way it should be used. FDA requires generic drugs have the same high quality, strength, purity and stability as brand-name drugs.
A matrix is a rectangular array of numbers arranged in rows and columns. The array of numbers below is an example of a matrix. The number of rows and columns that a matrix has is called its dimension or its order. By convention, rows are listed first; and columns, second.
Unit triangular matrix where all the diagonal are one. A lower triangular matrix is unit lower triangular if it has ones on the diagonal and each and every element above the diagonal element is zero. Unit lower triangular matrix is of the form: A = $\begin{bmatrix}1 & 0 &0 & . & . & 0\\a_{21}& 1 & 0 & .