Is Separating Negative Numbers in Math Valid?

[Delzac]

Hi all,

Just some interesting stuff to share.

Study = Don't Fail--------(1)
Don't Study = Fail--------(2)

Add (1) &(2)

Study + Don't Study = Don't Fail + Fail

Factorising the equation,

Study(1+Don't) = Fail(1+Don't)

Study = Fail !?!

:P

Delzac

 

[Gokul43201]

Dividing (1) by (2)
study/(don't study) = (don't fail)/fail
Hence 1/(don't) = don't
Or don't =1 or -1

If don't = -1
1+don't = 0
Division by 0 is illegal.

If don't =1 (the multiplicative identity), then (1) and (2), both become: study=fail,
which is not inconsistent with the final result.

 

[Delzac]

lol didn't notice thanks for the note

 

[Delzac]

hmm...if Don't = 1 then it takes the fun out of things already, but is can't be -1 also...zzzzz i will try think of a better equation. ^^

 

[ZapperZ]

Try this one (which is a rather old "puzzle")

1 = sqrt(1) = sqrt(-1*-1) = sqrt(-1)*sqrt(-1)=i*i=-1

so 1 = -1 !

[Now before people jump all over me on that, I KNOW where the fault is].

Zz.

 

[Mech_Engineer]

I've got a good one:

Women = Money * Time

Time = Money (Time is money!)

Women = (Money)^2

Money = sqrt(Evil) (Money is the ROOT of all evil...)

So, Women = Evil

Of course I've known this all along, I just have a mathematical proof of it now

 

[Delzac]

Nice one mech, how very true.

Anyway referring back to zapper, something must be wrong, but i just can't a hand to it. take this for example.

1 = sqrt(1) = sqrt( -1*-1) = sqrt( (-1)^2 ) = (-1)^(2/2) = -1 ??

For now i can't solve, i will get back to you later.

 

[Gokul43201]

The answer is simple, and exemplified by shortening the process some:

-a = sqrt(a^2) = a

 

[Delzac]

hmm...here's my initial thought.

X = sqrt ( (+-x)^2 ) there is something wrong with this step right?

 

[Gokul43201]

Yes, it's like saying: 0 = inv. sin (0) = pi

The square root (like the inverse sine) is not strictly a function, because it is a one-to-many mapping (functions, strictly, are may-to-one, or one-to-oe maps). These are sometimes, loosely called multiple valued functions, with the condition that a principal value is assigned to the image (like the positive square root) when it's not specified which image you are talking about.

 

[theCandyman]

Dividing (1) by (2)
study/(don't study) = (don't fail)/fail
Hence 1/(don't) = don't
Or don't =1 or -1

If don't = -1
1+don't = 0
Division by 0 is illegal.

If don't =1 (the multiplicative identity), then (1) and (2), both become: study=fail,
which is not inconsistent with the final result.

Hahaha! That has to be one of the best replies to a joke I have ever heard.

 

[Delzac]

can i also solve the problem by saying that: 1 = sqrt ( (-1)^2) = l -1 l = 1

is this explanation valid?

 

[Mk]

I think some of you are spending too much time on turning words and phrases into mathematical shenanigans.

 

[Delzac]

Anyway, When i ask my Math teacher about

" 1 = sqrt(1) = sqrt(-1*-1) = sqrt(-1)*sqrt(-1)=i*i=-1 ".
-------------------^^^^^------------------------
She says that it is not valid because if u have negative numbers in brackets, then u cannot separate them out, instead u must work them out 1st bacause negative numbers are special. which i feel is crap. But is her explanation correct?