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How is -4 divided by -4 = -8

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Original post by NoahMal
-4/-4 Firstly two negatives cancel out hence its 4/4 which is 1 therefore by mathematical induction it does not equal -8....


I mean that's not mathematical induction, but sure
Original post by 1 8 13 20 42
I thought it was undefined until this year and I'm a maths student lel. As far as I know it is generally accepted to be 1 but I can't recall why even though I have looked into it before.


I think it is??? i dunno have to look at the video again since it's supposed to be one of those "not possible" things just like a fractions with a demoninator of 0 isn't possible.
Reply 22
Original post by thegreatwhale
I think it is??? i dunno have to look at the video again since it's supposed to be one of those "not possible" things just like a fractions with a demoninator of 0 isn't possible.


I think it mainly boils down to the fact that it is more convenient to have it equal to 1. In one sense, it technically is undefined, but it makes things make more sense in areas like set theory and discrete maths to have it equal 1.
Original post by 1 8 13 20 42
I think it mainly boils down to the fact that it is more convenient to have it equal to 1. In one sense, it technically is undefined, but it makes things make more sense in areas like set theory and discrete maths to have it equal 1.


yea i guess :biggrin:
Original post by 1 8 13 20 42
I thought it was undefined until this year and I'm a maths student lel. As far as I know it is generally accepted to be 1 but I can't recall why even though I have looked into it before.


It is frustrating, but you can just use this simple workaround:

10=20=1 1^0 = 2^0 = 1

1=2 \Rightarrow 1 = 2

0=11=21=1 \Rightarrow 0=1-1=2-1=1

I believe this lemma makes what you've done perfectly rigorous.
Reply 25
its not
Original post by newblood
Erm no...


Erm It was a joke rit calm down you little mug hole Or ill throw a Charmander at you
Original post by Protoxylic
I mean that's not mathematical induction, but sure


It was a joke mate...
Reply 28
WAIT WHAT people, how can -4 / -4 be 1?! You're taking something less than zero and making it smaller and ending up with something greater than zero.

This is why I flopped Maths
Reply 29
Original post by abc:)
WAIT WHAT people, how can -4 / -4 be 1?! You're taking something less than zero and making it smaller and ending up with something greater than zero.

This is why I flopped Maths


u wot m8
Original post by NoahMal
Erm It was a joke rit calm down you little mug hole Or ill throw a Charmander at you


That was too subtle- nobody could see it- on a thread with such a 3rd grade question it's hard to see who's genuinely incompetent and who's kidding
I know it is a bit quiet on TSR but this is ridiculous
Reply 32
Assume that 4÷4=8-4 \div -4 = -8.

But 4÷4=1-4 \div -4 = 1.

CONTRADICTION

4÷48\therefore-4 \div -4 \neq -8
Original post by abc:)
WAIT WHAT people, how can -4 / -4 be 1?! You're taking something less than zero and making it smaller and ending up with something greater than zero.

This is why I flopped Maths


wtf?

how are you making it smaller?
Reply 34
Original post by Student403
wtf?

how are you making it smaller?


Because if you divide something, the new total is smaller. Half a pizza is smaller than a whole pizza... so I don't understand how -4 divided by anything can equal something greater than 0?


I don't do maths ok!!!! :colonhash:
Original post by abc:)
WAIT WHAT people, how can -4 / -4 be 1?! You're taking something less than zero and making it smaller and ending up with something greater than zero.

This is why I flopped Maths


Well, at least the last sentence makes sense


Posted from TSR Mobile
Original post by abc:)
Because if you divide something, the new total is smaller. Half a pizza is smaller than a whole pizza... so I don't understand how -4 divided by anything can equal something greater than 0?


I don't do maths ok!!!! :colonhash:


This is the part which is incorrect

That's like saying "if you add something, the new total is bigger". Not necessarily. What happens if you add a negative number?
Reply 37
Original post by drandy76
Well, at least the last sentence makes sense


Posted from TSR Mobile


Lol I'm being destroyed :laugh: I really need this explaining to me
Reply 38
Original post by Student403
This is the part which is incorrect

That's like saying "if you add something, the new total is bigger". Not necessarily. What happens if you add a negative number?


ohhhhh yeaaah.... penny drop! Thank you lol
Original post by Student403
This is the part which is incorrect

That's like saying "if you add something, the new total is bigger". Not necessarily. What happens if you add a negative number?


Technically speaking it is getting smaller if we're only concerned with the magnitudes


Posted from TSR Mobile

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