Show that 101 is prime in easiest possible way.....

Show that 101 is prime in easiest possible way.........

4 Answers

A number n > 1 is prime if it cannot be written as a product of two integers a and b, both of which are larger than 1:

n = a*b

or that it of the form 8k+1 if it is an odd number..

Sir, If I take k=3 ? It comes out 25 which isn't a prime number?

@Vivek : Exactly... Also if we put k = 1 then we get 9 which is not a prime...

@Nishant sir : The solution is from one of the books that u've sent me..

The solution is here:......

It is from the fact that if n is a composite number greater than 1 then it has prime
factors p < n

Now, âˆš101 â‰ˆ 10

and non of the prime numbers less than 10 i.e., 2,3,5,7 divides 101. Thus
101 is a prime number...

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