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1. End of Unit Test on Probability for S2 Students
2. End of Unit Test on Statistics of Grouped Data for S2 Students
3. End of Unit Test on Vectors for S2 Students
4. End of Unit Test on Pythagoras Theorem for S2 Students
5. End of Unit Test on Thales Theorem for S2 Students
6. End of Unit Test on Multiplier for Proportional Change for S2 Students
7. End of Unit Test on Simultaneous Linear Equations and Inequalities for S2 Students
8. End of Unit Test on Polynomials for S2 Students
9. End of Unit Test on Indices and Surds for S2 Students
Isometries Unit Summary
1. Isometry: this is a transformation which preserves shapes, appearance, size and area of the object. Examples of isometries are 1) Central symmetry, 2) Reflection, 3) Rotation, and 4) Translation.
2. Central symmetry: is fully defined if the object and the centre are known
* Object and image are identical, but are inverted
* \(A^{'}B^{'}C^{'}\) is the image of ABC by a rotation, 180 degrees about the centre (0,0).
* Object point, corresponding image point and centre are collinear.
3. Rotation: is defined [if given one point on the object and the centre and angle of rotation or
* Two point and their corresponding images.
* An angle of rotation can be stated as positive (anticlockwise) or negative (clockwise).
* Both object and image are described as being directly congruent.
4. Reflection
* We define a reflection by giving a point on the object and the mirror line.
* Object and image are identical but face opposite directions. They are said to be oppositely congruent.
* Corresponding points under reflection are equidistant from the mirror line and the line segment joining them meets the mirror line at 90 degrees.
* Points on the mirror line are invariant.
5. Translation: A translation is fully defined if:
* If the object and the translation vector is given or An object and corresponding image point are known.
* Under translation, points move equal distance in the same direction i.e. parallel.
* Both object and its image are identical and they are said to be directly congruent. They face the same direction.
6. Composite transformations
These are transformations that are performed successively on the same object. They are also known as combined transformations.