Minus one times minus one equals one?

[Norrie]

No I know why yer PC aint working

 

btw remember we are taking it up to visit Dr Nick

 

 

Must have been a BB thing, its all working perfectly well now !!!!!

[jabee]

I am sat at home with the flu, bored, f**k all on telly, so……..

 

-2 * -3 = (-1)(2)(-1)(3)

-2 * -3 =(-1)(-1)(2)(3)

-2 * -3=(-1)(-1)(6)

 

To solve this equation we must therefore know the value of (-1)(-1)

 

The solution that is applied in mathamatics is that the answer is +1, which can be confirmed in that any other answer simply would not work; if we applied an assumption that the answer was negative, then the distributive property of multiplication would give the following answer when solving the equation below;

Unfortunately, here I have to insert an assumption, being that, a positive number multiplied by negative number, gives a negative; This can be considered safe, in that it is proved by the equation 1*x=x, so 1*-1=-1.

 

So, using the 'incorrect' assumption that the product of two negative numbers is a negative;

 

(-1)(1+ -1) = (-1)(1) + (-1)(-1)

(-1)(0) = -1+-1

0=-2

 

Which is clearly wrong, therfore disproving the 'incorrect' assumption!

 

However, applying the correct assumption that –1*-1=1;

 

(-1)(1+-1) = (-1)(1)+(-1)(-1)

(-1)(0)=-1+1

0=0

 

So, going back to the first equation:

 

-2 * -3 = (-1)(-1)(6)

6 = 1*6

 

QED!

 

 

Och, Wish I was looking at old Sum books !!!!! I'm only going fishing...

 

And I'm stuck here with my Beechams powders

Edited December 1, 2006 by jabee

[The Flying Tench]

The solution that is applied in mathamatics is that the answer is +1, which can be confirmed in that any other answer simply would not work;

 

Interesting. There have been some nice demonstrations, but nothing that quite amounts to a proof; and I think you're saying that we define it to be so to give a system of arithmetic that works. I'm still struggling a bit, and I haven't got 'flu, so well done with the Beechams Powders!

[Dan]

Interesting. There have been some nice demonstrations, but nothing that quite amounts to a proof; and I think you're saying that we define it to be so to give a system of arithmetic that works. I'm still struggling a bit, and I haven't got 'flu, so well done with the Beechams Powders!

 

 

But surely maths is in fact a set of rules, and this is just one of those rules, you can show it mathematically just as you can show pythagoras's theorem works. that must be proof enough. I'm not sure why but I dont have a problemm with the concept that -1 times -1 is +1, but try and explain relativity and I'm b*ggered!! Interestingly tho at the end of the day everything in science boils down to maths.

 

Dan

[Norrie]

Shhhhhh, A guys trying to sleep !!!!!

[Norrie]

John, Gonny empty yer mail box....canny send a PM ....

[Trubshaw]

I am sat at home with the flu, bored, f**k all on telly, so……..

 

-2 * -3 = (-1)(2)(-1)(3)

-2 * -3 =(-1)(-1)(2)(3)

-2 * -3=(-1)(-1)(6)

 

To solve this equation we must therefore know the value of (-1)(-1)

 

The solution that is applied in mathamatics is that the answer is +1, which can be confirmed in that any other answer simply would not work; if we applied an assumption that the answer was negative, then the distributive property of multiplication would give the following answer when solving the equation below;

Unfortunately, here I have to insert an assumption, being that, a positive number multiplied by negative number, gives a negative; This can be considered safe, in that it is proved by the equation 1*x=x, so 1*-1=-1.

 

So, using the 'incorrect' assumption that the product of two negative numbers is a negative;

 

(-1)(1+ -1) = (-1)(1) + (-1)(-1)

(-1)(0) = -1+-1

0=-2

 

Which is clearly wrong, therfore disproving the 'incorrect' assumption!

 

However, applying the correct assumption that –1*-1=1;

 

(-1)(1+-1) = (-1)(1)+(-1)(-1)

(-1)(0)=-1+1

0=0

 

So, going back to the first equation:

 

-2 * -3 = (-1)(-1)(6)

6 = 1*6

 

QED!

And I'm stuck here with my Beechams powders

 

 

So how many vicars am I left with, given that I have 1 minus vicar and 1 plus vicar, 1 parrot, 1 pet shop owner, one x vicar, one y vicar and 1 z vicar??

 

This is a new deadly flu solution. The one that only affects the male of the species and never attacks the females.

Edited December 2, 2006 by Trubshaw

[jabee]

So how many vicars am I left with, given that I have 1 minus vicar and 1 plus vicar, 1 parrot, 1 pet shop owner, one x vicar, one y vicar and 1 z vicar??

 

This is a new deadly flu solution. The one that only affects the male of the species and never attacks the females.

 

The way i see it, you have [1*(x+y vicars)]+(pet shop)+(owner)+[parrot+(2*z)]; x and y being unknown variables, and z being strings of unknown length attached to legs of said parrot!

 

Edited December 2, 2006 by jabee

[jabee]

Interesting. There have been some nice demonstrations, but nothing that quite amounts to a proof; and I think you're saying that we define it to be so to give a system of arithmetic that works. I'm still struggling a bit, and I haven't got 'flu, so well done with the Beechams Powders!

 

In mathamatical terms, It has been proved in that the 'wrong' answer is disproved and then applying the correct answer to the first equation, thus proving it to be so.

 

To provide a proof in practical terms is quite difficult, in that we are applying thoery to events....Do not fall in to the trap of viweing a negative value as simply less than nothing. A negative value is a number within the framework of mathamatics theory.

 

In my example of an employer paying your tax, being expressed as the equation -12*-100=£1200. Who is to say definitively that the period in which the payments are made on your behalf should be expressed as -12, however, the expression;

 

-12 * -100 = £1200

 

does represent a reality in that you will have received £1200 worth of benefit for no cost!

 

-12 * 100 = £1200, or even 12 * -100 = £1200 is incorrect (remember this is proved incorrect by 1*x=x)

Edited December 2, 2006 by jabee

[corydoras]

This is not really even maths, just basic arithmetic. Rather than cloud the issue with my own botchy proof, I am just going to post a couple of links. Here is one to get you going.

 

 

Just for Dan, I've also posted the link to the Wikipedia article on Pythagoras' Theorem with some of its many proofs.

Edited December 2, 2006 by corydoras