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### Proving that 1 + 1 = 3

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Date: 11/18/95 at 23:50:57
From: Anonymous
Subject: 1+1 = 3 ?

Hi,

How can I show that 1+1 = 3 ?
There is a possibility if you use sin and cos,
but I don`t know how.

CU
```

```
Date: 11/19/95 at 17:12:23
From: Doctor Ken
Subject: Re: 1+1 = 3 ?

Hello!

Let me say first of all that there is no real proof for the statement
1 + 1 = 3.  You cannot use correct mathematics to prove an incorrect
statement.

However, there are a couple of cutesie "proofs" of stuff like this,
and you can use them to "prove" anything you want.  The most
famous example is the "proof" that 1 = 0, and once you prove anything
that isn't true, you can prove ANYTHING else.  You could prove that the
moon is made of green cheese.  You could prove that 5 = 8.  You could
prove that I'm your father.  And yes, you could also prove that 1+1 = 3.
That's because the statement p => q is always true when p is false.

So that's the deal.

-Doctor Ken,  The Geometry Forum
```

```
From: Anonymous
Date: 11/22/95 at 23:50:57
Subject: 1+1 = 3 ?

Can you give me a possible solution, an example?

CU
```

```
Date: 12/15/95 at 0:9:20
From: Doctor Ken
Subject: Re: 1+1 = 3 ?

Hello -

Here's one that's not too tricky to figure out where the problem is.
My  fellow doctor Ethan made it up:

Let x=y.  Then

x - y + y =  y

x - y + y    y
--------- = ---
x-y      x-y

y     y
1 + --- = ---
x-y   x-y

1 = 0

Now we know that 1 = 1, so add the following three equations together:

1 = 0
1 = 1
1 = 1

On the right is 1+1, and on the left is 3 ones, and 3 ones make 3.

-Doctor Ken,  The Geometry Forum

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