Try Work out this maths question ;) Watch

X1PRINCE
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#1
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Disprove this statement by providing a counterexample, n is an integer

"If n^3 is divisible by 8, then n is divisible by 8"
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RDKGames
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(Original post by X1PRINCE)
Disprove this statement by providing a counterexample, n is an integer

"If n^3 is divisible by 8, then n is divisible by 8"
n = 2
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X1PRINCE
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(Original post by RDKGames)
n = 2
Ha ha, don't look to me for the answer XD, I'm just a maths A level student trying to figure out what the answer and working out is to it lol. But if you input 2 the statement is right, however the question asks to disprove, I don't think it's simple as giving the number. Can you help me put this in the maths group please
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BillyMic
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I mean 2^3 = 8.
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WhatIsLife1
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(Original post by X1PRINCE)
Ha ha, don't look to me for the answer XD, I'm just a maths A level student trying to figure out what the answer and working out is to it lol. But if you input 2 the statement is right, however the question asks to disprove, I don't think it's simple as giving the number. Can you help me put this in the maths group please
The question states ‘by counterexample’. N = 2 is a counterexample
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RDKGames
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(Original post by X1PRINCE)
Ha ha, don't look to me for the answer XD, I'm just a maths A level student trying to figure out what the answer and working out is to it lol. But if you input 2 the statement is right, however the question asks to disprove, I don't think it's simple as giving the number. Can you help me put this in the maths group please
Er... no this is a very simple question and n=2 disproves it.

2^3 = 8 is divisible by 8

but 2 on its own is not divisible by 8.
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PepeIsAngry
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N = 4 as well lol.
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BillyMic
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(Original post by PepeIsAngry)
N = 4 as well lol.
Why 4 as 4^3 is 64?
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PepeIsAngry
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64 is divisible by 8 but 4 isn't.
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BillyMic
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(Original post by PepeIsAngry)
64 is divisible by 8 but 4 isn't.
Smart stuff, thanks for telling me.
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X1PRINCE
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Huh, that's wierd it's a 2 mark question lol XD.
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RDKGames
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(Original post by X1PRINCE)
Huh, that's wierd it's a 2 mark question lol XD.
One mark for a valid n value, and another for your reasoning. Probably. It's a typical weight for such a question.
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X1PRINCE
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(Original post by RDKGames)
One mark for a valid n value, and another for your reasoning. Probably. It's a typical weight for such a question.
Probably is, lol thanks. Looked at the A Level Paper thought it was going to be a big questions. Turns out it's a simple question
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