i made a question by myself here it goes:(adsbygoogle = window.adsbygoogle || []).push({});

proove that the only solution to p is 3:

n^2-1=p where n is a natural number and p is a prime number.

now im not sure about my proof so dont kill me (-:

from what we are given n^2-1 is a prime number which is (n-1)(n+1)

we all know that a prime number can only be divided by itself and by one therefore we can put it into options either n-1=1 and n+1=n^2-1 or n-1=n^2-1 and n+1=1

from the solutions of this equations we find the answers to n are:

2,-1,2,0,1,0 respectively.

now the only number which suits the equality is 2 and therefore p is 3.

what do you think? easy question?

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# Validity of a proof

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