Compiled by: Ms. Tiffany Givans AY 2019/20 SEM22As shown matrices are denoted either by boldface letters (A) or by italic lettersenclosed within brackets ([A]).The quantities forming a matrix is referred to as itselements. The elements ofa matrix are usually numbers, but they can be symbols, equations, or evenother matrices (called submatrices). Each element of a matrix is represented bya double-subscripted letter, with the first subscript identifying the row and thesecond subscript identifying the column in which the element is located. Thus,above A23represents the element located in the second row and third column ofmatrixA. In general,Aijrefers to an element located in theith row andjthcolumn of matrixA.The size of a matrix is measured by the number of its rows and columns and isreferred to as theorderof the matrix. Thus, matrixAabove, which has m rowsand n columns, is of orderm × n(mbyn). As an example, consider a matrixDgiven by𝐷 = ൦35378−60122327−9−1൪The order of this matrix is4 × 3, and its elements are symbolically denoted byDijwithi= 1 to 4 andj= 1 to 3;for example, D13= 37,D31= 12,D42= −9, etc.TYPES OF MATRIXSome of the common types of matrices in the following paragraphs.Column Matrix (Vector)If all the elements of a matrix are arranged in a single column (i.e.,n= 1), it iscalled acolumn matrix. Column matrices are usually referred to as vectorsand are sometimes denoted by italic letters enclosed within braces. An exampleof a column matrix or vector is given by