Pi Day

March 14 is Pi Day - 3.14 ...... 

Fun anti-Pi rant from the Khan Academy - actually there is a lot of serious maths in here!

Happy Pi Day.



Anti-Pi Rant, 3/14/14: Sorry, Pi lovers! Maybe pick a better favorite number next time?

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Integers

After the Natural numbers we next meet the Integers.

The Integers include all the whole positive and negative numbers and zero

We use N to stand for the set of Natural numbers but surprisingly we use Z to stand for the set of of Integers - this comes from the German for "number". This picture was taken in the German classroom.

Prime Numbers

The primes between 1 and 100

2	3	5	7	11
13	17	19	23	29
31	37	41	43	47
53	59	61	67	71
73	79	83	89	97

 Here is the 1M poster, for Maths week, of the primes less than 100.

 

LCM & HCF

The following pencast shows you how to use the product of prime factors to find the HCF or LCM of two or more numbers.

This is very useful, especially for large numbers.
LCM - pick the highest power of each prime factor and multiply together.

HCF -  pick the lowest power of the common prime factors and multiply together.

HCF and LCM with Prime Factors
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Product of Prime Factors

If we take any number that is not a prime number we can write it as the product of 2 or more prime numbers. This means it can be made by multiplying prime numbers together. 

Click below to watch some examples using the "factor tree" method. Click the yellow arrow to make it bigger, you can jump backwards and forwards by clicking anywhere on the page.

Starter Notebook p. 13
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You can break these down in lots of different ways but the final answer will always be the same.

Remember: Product means "multiplied together".
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