Can primes be negative?

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Can primes be negative?

by RumpelThickSkin » Wed Aug 04, 2010 3:12 am
Can somone please clarify for this for please

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by saritalr » Wed Aug 04, 2010 4:16 am
RumpelThickSkin wrote:Can somone please clarify for this for please
According to my prep book: "A prime number is any positive integer larger than 1 with exactly 2 factors: 1 and itself"

A quick google search makes me think that there might be some grey zone at a more advanced theoretical level - but for the GMAT (and for most other purposes), I think the answer is no - primes are positive.

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by bdevas01 » Wed Aug 04, 2010 5:41 am
Nope, primes by definition are positive.

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by lunarpower » Fri Aug 06, 2010 3:45 am
doesn't really matter -- you will never have to deal with this issue, one way or the other, on an official problem.
no way.

the problems will almost certainly say something like "positive prime number", making it explicit. if they don't, then there will be some other context that implies or requires the primes in question to be positive.
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by Abhishek009 » Fri Aug 06, 2010 8:16 am
RumpelThickSkin wrote:Can somone please clarify for this for please
Well this link is just for knowledge https://mathforum.org/library/drmath/view/55940.html have a look at this.
Abhishek

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by neerajbansal » Sat Aug 07, 2010 6:50 pm
prime has 2 factors...

the number itself and 1

so for a negative number say -7

the factors are

1 -7 and -1 ==> three..

violates the definition of a prime

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by sanju09 » Mon Aug 09, 2010 3:40 am
RumpelThickSkin wrote:Can somone please clarify for this for please
Whenever we come across the terminologies like, primes, composites, divisors or factors, etc, they customarily mean positive integers only, with no ambiguity whatsoever. I haven't ever learnt a term like "positive prime number" on real GMAT.
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by sanju09 » Mon Aug 09, 2010 4:25 am
RumpelThickSkin wrote:Can somone please clarify for this for please
What is this extra for for?
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