Notes, 11mat02 13-8-14
Describing Transformations
· Always name the object (eg. tile 1) and the image (eg. tile 2) as part of your description.
· Name the invariant points too for a better mark.
Reflection
· To describe a reflection, you must also describe the mirror line.
· The invariant points for reflection are on the mirror line.
Rotation
· To describe a Rotation, you must also give:
o The centre of rotation – eg the top RH corner of tile 1
o The angle of rotation – eg 90
o The direction – eg clockwise.
· The centre is the only invariant point.
Translation
· To describe a Translation, you must also give:
o The distance moved left/right
o The distance moved up/down
And/or
o The vector
· There are no invariant points for translation.
Describing Transformations
· Always name the object (eg. tile 1) and the image (eg. tile 2) as part of your description.
· Name the invariant points too for a better mark.
Reflection
· To describe a reflection, you must also describe the mirror line.
· The invariant points for reflection are on the mirror line.
Rotation
· To describe a Rotation, you must also give:
o The centre of rotation – eg the top RH corner of tile 1
o The angle of rotation – eg 90
o The direction – eg clockwise.
· The centre is the only invariant point.
Translation
· To describe a Translation, you must also give:
o The distance moved left/right
o The distance moved up/down
And/or
o The vector
· There are no invariant points for translation.