‫بسم هللا الرحمن الرحيم‬
Umm Al-Qura University
Health Sciences College at Al-Leith
Department of Public Health
Lecture (7)
Objectives:
1/ Define Matrix Types.
2/ Give an Example of Matrix Types..
 Types of matrices



 Upper triangular matrix:
 A mxn matrix for which aij = 0, i>j is called an
upper triangular matrix. That is, all the elements
below the diagonal entries are zero.
 Example:
 Give an example of an upper triangular matrix
 Solution
 A=
 Lower triangular matrix:
 A mxn matrix for which aij = 0, j > i is called a
lower triangular matrix. That is, all the elements
above the diagonal entries are zero.
 Example:
 Give an example of a lower triangular matrix
 Solution

 A=
 Diagonal matrix:
 A square matrix with all non-diagonal elements
equal to zero is called a diagonal matrix, that is, only
the diagonal entries of the square matrix can be nonzero,(aij = 0, i ≠ j).
 Example :
 Give examples of a diagonal matrix.
 Solution

 Identity matrix:
 A diagonal matrix with all diagonal elements
equal to one is called an identity matrix, (aij = 0, i≠j;
and aii = 1 for all i).
 Example
 Give an example of an identity matrix.
 Solution
 A=
 Zero matrix:
 A matrix whose all entries are zero is called a zero
matrix, (aij = 0 for all i and j).
 Example
 Give examples of a zero matrix.
 Solution


Thanks
Radia