Matrices

Multiplying matrices

Identity matrix

When used as a transformation matrix

No movement occurs

Transformations

Reflections

Reflection in x-axis	Reflection in y-axis
Reflection in y=x	Reflection in y=-x
Reflection about origin	–

Rotation

(Rotation is anticlockwise if not specify)

 

Rotation 90° anticlockwise about origin	Rotation 180° anticlockwise about origin
Rotation 270° anticlockwise about origin	–

Enlargement

Scale factor 2 centre origin

Examples

Work out the image of point (-2,5) for the

transformation defined by

∴ The image point is (11,9)

Mark Scheme

Mark Scheme