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