Sunday, March 30, 2008

Surds, Indices and Index Notation

In the last classes we looked at these topics and I gave you all a handout of all the related questions from previous Junior Cert papers.
If you can do all of these you will have no problems with this topic in your exam.
In Monday's class we will go over these questions and get ready spend the remainder of this week and all of next week on algebra.

Tuesday, March 11, 2008

Co-ordinate geometry

This topic is examined on Paper 2 in question 2.
You need to apply the concepts of translations and symmetry on the co-ordinated plane.
You also need to remember all the formulae and be able to apply them.
This is an overview of how the connections between the different concepts of midpoint, distance, slope and equation of a line.

Sunday, March 2, 2008

Sets

We looked at Set notation, basics of Venn diagrams etc in class. If you are unsure of any of this, go back over the Sets chapter in book 1, as book 2 really just glosses over the foundations.

The big difference with Higher Level Sets is that you have to handle unknowns.
Take a class where 8 study Latin and 10 study Business. If you don't know how many study both, you put :
x in the L intersection B region of the diagram
(8 - x) in the L\B region
(10 - x) in the B\L region.
Then if you are told there are 14 students altogether you can create the equation:
(8 - x ) + x + (10 - x) = 14
and solve for x
18 - x = 14
x = 4 .... so 4 students study both Latin and Business.
You don't need the brackets in the above example, but it is a good idea to always use them as there are times you need to work out expressions like in q 13 on page 195
For the region of the Venn diagram representing W only the x - 2 is worked out from:
16 - (10 - x) - x - (8 - x)
= 16 - 10 + x - x - 8 + x
= -2 + x or x -2

Homework was p189: q11, q13