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# As level maths q help watch

1. Prove that n² - 79n + 1601 is not always prime when n is a positive whole number
Got any ideas of numbers that might work (hint: the easiest one to spot is related to the numbers in the equation)
3. (Original post by Pastelx)
Got any ideas of numbers that might work (hint: the easiest one to spot is related to the numbers in the equation)
I'm not sure, I know that they are prime but what. umbers should I use in particular?
4. (Original post by Zain786H)
I'm not sure, I know that they are prime but what. umbers should I use in particular?
Okay, you know they are all prime and you have to find a number for n, which you can then square, multiply by something and then add a prime number to.

The thing you have to make sure of is that your answer is a multiple of 1601 (multiplying and squaring means the number won't be prime, so you don't have to worry about that)

Hence what value of n (the simplest value) is a multiple of 1601? –not a trick question!
5. (Original post by Pastelx)
Okay, you know they are all prime and you have to find a number for n, which you can then square, multiply by something and then add a prime number to.

The thing you have to make sure of is that your answer is a multiple of 1601 (multiplying and squaring means the number won't be prime, so you don't have to worry about that)

Hence what value of n (the simplest value) is a multiple of 1601? –not a trick question!
I understand now, thanks a lot, I subbed in 1601 as n so the product of the equation isn't prime and I believe 1523 and 1601 are the factors
6. (Original post by Zain786H)
I understand now, thanks a lot, I subbed in 1601 as n so the product of the equation isn't prime and I believe 1523 and 1601 are the factors
Good good! Np

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