1 = -1?!

[ILPPendant]

I posted this on the notice board of my university maths department. It took four days for someone to point out what went wrong. Let's see how the Escapist forum denizens fare.

Spoiler: It's a bit more complicated than this

Isn't anime wonderful?

 

[Redingold]

Now, I haven't the foggiest idea as to what the first bit means, but that algebra is annoying. It doesn't work! RAGE!!!!!!!!

I hate maths that doesn't work...

 

[stormcaller]

It's wrong because I say so.

Thank you *bows* *Catches roses thrown at him* *Runs before they start with the panties*

I'm sorry, I should've let Max do the derailing.

 

[JC175]

I think my brain just froze.

I'm planning on forgetting maths, personally.

 

[Ancalagon]

I give up. Thought the picture was funny, though.

 

[Gaskell]

I can prove this to be wrong with a demonstration

I have one mobile phone in my right hand
In my left hand I have 0 mobile phones
I move the phone from my right hand to left, minusing the 1, leaving my with 0 phones in my right hand, but now having one phone in my left
the 1 and zero are constant

 

[ILPPendant]

Well, obviously there's a flaw somewhere in there. A proof can't make something true, it just... proves it.

 

[Dragon_of_red]

Oh god I'm in year 10 Methods class, i cant do this, gimme a few years and i might be able too.

 

[Aardvark Soup]

I'm not very familiar with imaginary numbers like i (of which I only now it's the square root of -1) and I don't know the two formulas used here. However, after having looked that up on Wikipedia this seems to be right. I have no idea where the flaw is, but it's probably some limitation on using i.

 

[Zombie_Fish]

I can prove this to be wrong with a demonstration

I have one mobile phone in my right hand
In my left hand I have 0 mobile phones
I move the phone from my right hand to left, minusing the 1, leaving my with 0 phones in my right hand, but now having one phone in my left
the 1 and zero are constant

Ah, but that's different in algebra. In algebra, it would be something like this:

0=x (I'm using x instead of 1 as that just wouldn't make sense)

minus x

-x=o Which works as x=0 and there is no negative 0, so -x must also equal zero, because in algebra, what you do to one side must be done to the other. So in your example, you would have to take away a mobile phone from your left hand as well.

Spoiler: It's a bit more complicated than this

Isn't anime wonderful?

I don't like that sum, as it solves out to 26=0 (I'm only doing GCSE maths currently, so the University one's a bit out of my league)

 

[Anachronism]

I hate maths. Not even in the face of armageddon will I compromise in this.

This is neither the time nor the place for it.

Hell, it's never the time or the place for it.

 

[RetiarySword]

I posted this on the notice board of my university maths department. It took four days for someone to point out what went wrong. Let's see how the Escapist forum denizens fare.

Spoiler: It's a bit more complicated than this

Isn't anime wonderful?

I'm only at first year uni maths, but maybe you can help me with my maths assignment??

 

[Dys]

Second line after "raise both sides to pi/x" doesn't make sense to me. Not sure if that's the flaw but I'd be using a logarithm to solve that (might be what you've done, but I've already spent too much of my time doing this instead of structural mechanics to bother checking).

 

[Doug]

First line is wrong. e^ix is not always = 1. You've made the mistake of cos x + sin x = 1, when its cos^2 x + sin^2 x == 1.

Also, there is an i on the sin that you seem to have completely ignored.

EDIT:
Also, e^ix for all x IS NOT = cos 2pi + sin 2pi. Its e^ix = cos x + i sin x, if I remember my maths correctly.

 

[ILPPendant]

First line is wrong. e^ix is not always = 1. You've made the mistake of cos x + sin x = 1, when its cos^2 x + sin^2 x == 1.

Also, there is an i on the sin that you seem to have completely ignored.

EDIT:
Also, e^ix for all x IS NOT = cos 2pi + sin 2pi. Its e^ix = cos x + i sin x, if I remember my maths correctly.

Your challenge is only valid if x is something other than what I've defined it to be in the first two lines.

EDIT: Notice line three states for all x in X, not for all x in R or N.

 

[tk1989]

There are loads of different algebraic equations which can be done in which 1=0 or 1=-1. They are perfectly sound mathematically, but only that...

Just remember, its only an equation! Its not real!!!! 1 does not actually equal -1!

 

[ThreeWords]

I do not understand the maths, but there's a simple way to prove it's wrong, known as reducto ad absurdum (I think) or proof by contradiction.

Fact: 1=/=-1 (as can be observed in real life)

The very fact that the answer is incorrect proves the reasoning to be false.

 

[Vohn_exel]

Someone once asked me to explain at what point in time I'd be able to use the catchphrase "The Square Root of Nine is Three!" I forgot to respond and never answered them. This thread is just such an occasion

 

[ILPPendant]

Guys, I know it's wrong. That's not the purpose of this thread. I'm trying to see if anyone can spot the precise point at which the mathematics breaks down and we end up with the incorrect conclusion.

 

[AtticusSP]

1 = -1?
Holy shit, I think you just predicted the next Bleach plot twist.