May
11
Circle theorems
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There are seven theorems for you to discover and prove.
- Go to this page to discover seven hypothesis.
- Go to this page to see the seven theorems summarised.
- Come up with seven proofs and put them, with your name, as comments below.
May
10
Shear transformations
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There are two kinds of shears.
1. Horisontal shear.
All points are moved horisontally, i.e. the y-value does not change. How much a point is moved horisontally is proportional to its distance from the x-axis.
In short: (x, y) -> (x + ky, y).
k is called the shear factor. The x-axis is called the invariant line.
2. Vertical shear
All points are moved vertically, i.e. the x-value do not change. How much a point is moved vertically is proportional to its distance from the y-axis.
In short: (x, y) -> (x, y + kx).
k is called the shear factor. The y-axis is called the invariant line.
Question:
What kind of shear maps triangle X to triangle S? What is the invariant line? What is the shear factor?
May
9
Eating your cake and having it – Part 2
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Investigating:
By choosing a suitable unit you should be able to find how big each piece is.
——
Compare what you found with the image below.
Can you solve the mystery now?
May
9
Eating your cake and having it – Part 1
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The problem:
James Tanton has made a video where he eats a piece of a cake. The white square below.
Carefully rearranging the pieces that are left he manages somehow to make the cake whole again!
Voila!
Please explain how this is possible.
May
9
Khan x 2
Filed Under Learning, Teaching, Video | Leave a Comment
Khan interviewed by Charlie Rose last week.
On the usefulness of Khan’s videos.