## Thursday, January 21, 2010

### Task 1: followup from Locker Exercise

Dear wonderful 109ians,

Thank you for your comments on the Locker question. It is certainly an introductory lesson on our first chapter on HCF and LCM.
1. Composite Numbers
2. Prime factorisation
3. Index Form
• simple comments (to this blog entry)
• use reference from your Maths e-textbook or any other reliable Maths books
• include reliable you-tube on this topics (pls quote source)
• maths dictionary
• sample examples from reliable resources to illustrate your understanding of subtopics
It is important that
you collaborate as a class to reinforce or correct one another
support your friends with examples etc.

1. First Comment From Mr Jo
1.Prime number (this will help with Prime Factorisation)
It is a positive integer which can only be divided by the number 1 and itself. The number 1 is not a prime number.
Check Sieve of Erastosthenes @ http://en.wikipedia.org/wiki/Sieve_of_Eratosthenes
and try yourself @
http://www.hbmeyer.de/eratosiv.htm

2. Hi everybody, Preston here.
1. A composite number is a positive integer that has factors other than just 1 and the number itself. (Opposite of prime number)
2. A prime factorization is the meaning of writing an integer as a product of powers of prime numbers.
3. An index form is where a number is expressed using exponents (one number to the power of another).

Sources: Math dictionary

3. I found a video about Prime Factorisation

4. For any queries we can also check out Yourteacher.com mathteacher.com www.mathsisfun.com
Another video abt prime fratorisation:
Index form we can try:
http://www.mathsteacher.com.au/year10/ch08_indices/01_index_form/form.htm
A video abt index form:
Composite no. :
http://www.mathsisfun.com/prime-composite-number.html
video:

Davina

5. Slideshows
The slideshow for the composite numbers tells us how to differentiate between prime and composite numbers. In the index form slideshow the '.' is multiplication.
Prime Factorisation:
http://www.slideshare.net/guest8e9b21/prime-factorization-2101516
Composite numbers:
http://www.slideshare.net/taleese/prime-numbers-472705
Index Form:
http://www.slideshare.net/josesayago/index-form

6. 1.)Composite Number

A positive(greater than 0) integer that has factors other than 1 and the number itself(Not a prime number). For example, 4,6,8,9,10,12,etc. are all composite numbers. The number 1 is not composite.

2.)Prime Factorisation

"Prime Factorization" is finding which prime numbers you need to multiply together to get the original number.

3.)Index Form

Index form is where a number is expressed using exponents - one number to the power of another.
For example, 2x2x2x2x2 is the same 2 to the power of 5, written as 25.

7. Hi
1.) A composite number is a integer greater than 0 that has factors beside 1 and itself. 0 and 1 are neither composite nor prime numbers.

2.) Prime factorization is finding out which primes you need to multiply to get the original number.
Ex: 170=2x5x17

3.) A Index form is a subscript or a superscript used to indicate powers.

8. Let me share with you my views :

1) A composite number is a number that has factors in addition to one and itself. All even numbers are divisible by two, so all even numbers greater than two are composite numbers. All numbers that end in five are divisible by five, so all numbers that end with five and are greater than five are composite numbers.

2) Prime factorization is when factors of a number are prime numbers, and when one is multiplied, the answer is that of the original number.

Example : The factors of 15 is 1, 3, 5 and 15 itself, both 3 and 5 are prime numbers, and 3 times 5 is equivalent to 15.

3) Index form is where a number is expressed using exponents (a quantity representing the power to which a given number is to be raised, one number to the power of another).

For example, 2 times 2 times 2 times 2 is the same as 2 to the power of 4, it is written as : the 4(quantity) is written smaller and above the 2(number to be raised).

See To Yu Xiang

Sources : http://www.aaastudy.com/fra63ax2.htm
http://www.mathsisfun.com/definitions/prime-factor.html

9. Hi this is Niklaus.Here is what i found out
1.A number that is a the product of at least two numbers other than itself and 1
2.Prime Factorization" is finding which prime numbers you need to get the longest possible multiplication problem to get a certain number.
EG: The certain number is 12, so in order to get the longest possible multiplication, you must like divide the number to get many numbers and multiply them to get 12. Answer:2x2x3
3.Index form is where a number is expressed using exponents - one number to the power of another.EG:2x2x2x2x2x2x2x2, there is 8 x2, so to you write that 2 to the power of 8.

10. Composite Numbers:
A composite number is a positive integer which has a positive divisor other than one or itself.

Prime factorisation:
Prime factorization is the breaking down of a composite number into smaller non-trivial divisors, which when multiplied together equal the original integer.

Index Form:
Index form is where a number is expressed using exponents. (One to the power of another)