The fact that 2 was once not viewed as a prime number was described in the German book. Tropfke, J. Geschichte der Elementar-Mathematik, Band 1. Berlin, Germany: p. 96, 1921. Can any one provide a few English translations of sentences from that book that explains how was 2 not viewed as a prime in the past?
Can any one provide another source for the fact that 2 was once not a prime?
2006-08-10 12:25:38 · 6 answers · asked by shuangtheman 1 in Science & Mathematics ➔ Mathematics
Can you provide the German text? Then I may help with the translation.
2006-08-10 12:30:36 · answer #1 · answered by Stanyan 3 · 1⤊ 1⤋
Since 2 is only divisable by itself and one, it is by definition a prime number. Previously, 2 was not thought to be a prime number because no even numbers are prime and 2 is part of the set of even numbers.
2006-08-10 19:50:00 · answer #2 · answered by Anonymous · 0⤊ 0⤋
i can see 2 as not being prime since it is an even number. thats the only logical reasoning i could think of.
every other prime number out there is odd because the even numbers are all divisible by 2.
2006-08-10 19:34:20 · answer #3 · answered by pevehead 4 · 0⤊ 0⤋
This is true. Additionally, it was once thought that 1 was a prime number, even though today it is not thought of as such.
2006-08-10 20:52:45 · answer #4 · answered by Anonymous · 0⤊ 0⤋
Ja ja! The German text would help.....
But there is a short explanation and reference in English on:
http://mathworld.wolfram.com/PrimeNumber.html
2006-08-10 19:55:18 · answer #5 · answered by Marianna 6 · 0⤊ 0⤋
It is provin that 2 is the only prime numbe!
2006-08-10 19:30:30 · answer #6 · answered by Anonymous · 0⤊ 1⤋