Vicky Tran
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Just done the first paper of AS math 2019 [sign]

Can anyone explain to me how did you do question 16: Prove that n^3+2 is not divisible by 8.
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mani93786
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Natural numbers can be expressed as n^2+1 since they have to be bigger than 0.
(n^2+1)^3 + 2 = (n^6+3n^4+3n^2+1) + 2= n^6+3n^4+3n^2+3. There is no multiple of 8 ∴ not divisible by 8.
Not sure if this is correct tho
Last edited by mani93786; 1 year ago
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zetamcfc
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(Original post by Vicky Tran)
Just done the first paper of AS math 2019 [sign]

Can anyone explain to me how did you do question 16: Prove that n^3+2 is not divisible by 8.
n can be odd or even. Assume the statement is false then arrive at a contradiction.
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