## Monday, January 25, 2010

### Class Task : Factors & Multiples

Please use your learning device to source for information on the following:

1. A man named Erastothenes (Ren Chang's grp)
2. Erastothenes Sieve (Imran's grp)
3. All the Primes less than 1000 (Christian's grp)
4. Mersene Prime (Aaron's grp)

Prime Quiz (PART 1) for all as hw

#### 9 comments:

1. Eratosthenes of Cyrene (Greek Ἐρατοσθένης; c. 276 BC[1] – c. 195 BC[2]) was a Greek mathematician, elegiac poet, athlete, geographer, and astronomer. He made several discoveries and inventions including a system of latitude and longitude. He was the first Greek to calculate the circumference of the earth (with remarkable accuracy), and the tilt of the earth's axis (also with remarkable accuracy); he may also have accurately calculated the distance from the earth to the sun and invented the leap day.[3] He also created a map of the world based on the available geographical knowledge of the era. In addition, Eratosthenes was the founder of scientific chronology; he endeavored to fix the dates of the chief literary and political events from the conquest of Troy.
According to the entry Ἐρατοσθένης in the Suda (ε 2898), his contemporaries nicknamed him Βῆτα (beta, the second letter of the Greek alphabet) because he supposedly proved himself to be the second best in the world in almost any field.[4]

Source:http://en.wikipedia.org/wiki/Eratosthenes
/wikipedia

Group members: Tse tzang, Bing jue, Jit Sheng, Ren chang, Ethan , Eunice

2. Source 1:http://en.wikipedia.org/wiki/Eratosthenes_Sieve
Source 2:http://www.hbmeyer.de/eratosiv.htm

What is Erastothenes Sieve?
-It is a system to find all prime numbers up to a specified integer.
Source: Wikipedia

3. http://www.infoplease.com/ipa/A0001737.html

2, 3, 5, 7 ,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73 79 83 89 97 101 103 107 109 113
127 131 137 139 149 151 157 163 167 173
179 181 191 193 197 199 211 223 227 229
233 239 241 251 257 263 269 271 277 281
283 293 307 311 313 317 331 337 347 349
353 359 367 373 379 383 389 397 401 409
419 421 431 433 439 443 449 457 461 463
467 479 487 491 499 503 509 521 523 541
547 557 563 569 571 577 587 593 599 601
607 613 617 619 631 641 643 647 653 659
661 673 677 683 691 701 709 719 727 733
739 743 751 757 761 769 773 787 797 809
811 821 823 827 829 839 853 857 859 863
877 881 883 887 907 911 919 929 937 941
947 953 967 971 977 983 991 997
Zach,Eugene,Christian,Norman,Michelle,Celine

4. A mersene prime is a prime number follows this equation 2n-1.And "n" must be a prime.For example,127 is a mersenne prime.2 to the power of 7 -1 is 127.

Group 1:Kristin,Kang Yan,Jun Hao,Jun Peng,Wen Kai and Aaron

No source

5. I scored 10 out of 10 for the quiz

6. well done Kristin - how about the rest?

7. Lucky Kristin, I only score 8 out of 10 for the quiz.
Jing Heng

8. I got 8-10 too.

Aaron Sng Li Wen

9. I got 10 out of 10 for the quiz

tse tzang