MATRICES NADEEM UDDIN ASSOCIATE PROFESSOR OF STATISTICS https://www.slideshare.net/NadeemUddin17 https://nadeemstats.wordpress.com/listofbooks/
Introduction: The idea of matrices was introduced by a famous mathematician Arther Kally in 1857. Matrices is a subject that has wide application in the field of mathematics. A matrix is a square/rectangular array of numbers written within square brackets in a definite order, in rows and columns.
Order of a Matrix If there are ‘r’ rows and ‘c’ columns in a matrix A, then the order of the matrix is r x c. Order of matrix A is 2 x 2
Types of matrices (1)Rectangular Matrix If the number of rows and number of columns in a matrix are not equal the matrix is called a rectangular matrix. For e.g , ,
(2)Column Matrix If a matrix has only one column, it is called a column matrix or column vector. For e.g , ,
(3)Row Matrix If a matrix has only one row, it is called a row matrix or row vector. For e.g , (4) Square Matrix If the number of rows and columns in a matrix are equal, the matrix is called square matrix. For e.g ,
(5) Diagonal Matrix A square matrix with all its elements zero, except elements in the leading diagonal, is called a diagonal matrix. For e.g , , ,
(6) Scalar Matrix A diagonal matrix, all whose leading diagonal elements are equal is called a scalar matrix. For e.g , , ,
(7) Null matrix OR Zero Matrix A matrix all of whose elements are zero, is called a null matrix. For e.g , , ,
(8) Unit Matrix A diagonal matrix in which the leading diagonal elements equal 1 is called a unit or identity matrix. A unit matrix is denoted by the symbol ‘I’. For e.g ,