Wednesday, February 17, 2010

Form 5/Topic 3 - COMBINED TRANSFORMATION

This is just a revision topic from Form 2 and Form 3 with a little funny theory:
If C = TR, you do R first.
Meaning, when you combined 2 transformations T and R, you do R first, the second one.
The real problem is:
Form 5 students tend to forget what is taught in Form 2 and Form 3 !!
So, a little bit of revision will do.

There are 4 types of transformation (Malaysian syllabus):
1. Translation
2. Reflection
3. Rotation
4. Enlargement

1. TRANSLATION.
This is the one that is similar to the movements along the x-axis and y-axis (Cartesan plane). A Translation is the movement to the right (positive) or to the left (negative), followed by movement upwards (positive) or downwards (negative).

2. REFLECTION.
Reflection is done in a line. The line can be horizontal (y = c) or vertical (x = a) or slanting (y = mx + c). You need to know the equation of the line where the reflection is done. Sorry, no short cuts !!!

3. ROTATION.
Rotation is described with the angle, direction (clockwise or anti-clockwise) and the center of rotation (coordinates x,y). This is the most difficult of all the four types of transformations.

4. ENLARGEMENT.
Easy to detect but sometimes difficult to described. An Enlargement must describe the scale factor (how many times the object is enlarged) and the center of enlargement.
There is another formula used, i.e. the area of the image:
Area of Image = the square of k x Area of object.
[k is the scale factor]

Note:
In the SPM, there will be 2 or 3 questions in Paper 1
In Paper 2, there is a full 12-marks question in section B.

No comments: