Introduction to Matrices
Revise Matrices unit from G.C.E. (A/L) Combined Mathematics and G.C.E. (O/L) Mathematics.
Types of matrices
Square matrix
Number of columns equal to number of rows.
Diagonal matrix
A square matrix whose only non-zero elements are main-diagonal elements. Denoted
by
Identity matrix or Unit matrix
A diagonal matrix whose diagonal elements are all equal to
Zero matrix / Null matrix
All elements are
Column matrix (column vector)
Only
Row matrix (row vector)
Only
Triangular matrix
Upper triangular matrix or lower triangular matrix.
Upper triangular matrix
All elements below the main diagonal are
Lower triangular matrix
All elements above the main diagonal are
Matrix operations
Addition and subtraction
Order of the 2 matrices must be same. Matrix obtained by adding or subtracting corresponding elements.
Scalar multiplication
Matrix obtained by multiplying all elements by the scalar.
Matrix multiplication
Explained on a separate page: Matrix multiplication