Matrices

MATRICES

By : KassKassMaths​

​General Mathematics Syllabus. Section #9

Objective Nos ​7 - 13

TABLE OF CONTENTS

Definitions ​- Slide 3

Formalizing a matrix - Slide 4

Adding and subtracting Matrices - Slide 5

Identity Matrix - Slide 6

Scalar Matrix - Slide 7

Multiplication - Slide 8

Equal Matrices - Slide 12

Determinant of a 2 x 2 matrix - Slide 13

2 x 2 adjoint matrix - Slide 14

Inverse of a non-singular 2 x 2 matrix - Slide 15

Matrix and simultaneous equations ​- Slide 16

Reflection - Slide 18

Rotation - Slide​ 20

Enlargement - Slide 21​
Past Paper Questions to Practice - Slide 23

Definitions

1. A matrix is a rectangular array of numbers, written within a pair of square or curved brackets.

2. It is named using a capital letter.

3. If a matrix has "m" rows and "n" columns, its order is said to be "m by n" written as m x n. That is, the order of a matrix is the number of rows times the number of columns.

Formalizing a matrix

​Name	socks​	shoes​	bats​
Mark​	5​	3​	6​
Leo​	4​	7​	2​

Adding and subtracting Matrices

Identity Matrix

Scalar Multiplication

Multiplication

Examples

Equal Matrices

Determinant of a 2 by 2 matrix.

2 x 2 adjoint matrix

Inverse of a
non-singular 2 x 2 matrix.

Matrices and simultaneous equations.

Steps :

1. Put the equations in matrix form. (AX = B)

2. ​Determine the inverse of the coefficient Matrix. (A^-1)

3. Make matrix X , with unknown values, the subject​. ( X = A^-1 B)

4. Solve for unknown constants.​ (Multiply the 2 matrices and equate corresponding values)

   Where A is the coefficient matrix,

   X is the unknown variables matrix and

   B is the result/answers matrix.

Reflection

Rotation

Enlargement

Past Paper Questions to Practice

May/June 2024 Nos. 10 (a), (b)
May/June 2023 Nos. 10 (a), (b)
May/​June 2022 No. 10 (a) & (b)

​July 2021 No. 10 (a) & (b)

​May/June 2019 No. 10 (a)