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It's Paradoxical!
Topic Started: Dec 3 2006, 05:00 AM (746 Views)
Admin
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Admin
What I will do for you now is find a real solution to the equation

Posted Image.

Impossible, you might say. Well, watch.

First, we square both sides:

Posted Image

And then write it out:

Posted Image

Cancel....

Posted Image

Posted Image

And we have actually solved for Posted Image!

:shocked:

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Your job: find the one thing that prevents the answer I found from being a valid solution.


(You'll sorta notice that -3/2 dosen't work if you put in in the original equation)
Posted Image
Posted Image
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Noah
Neophyte
[ *  * ]
This is probably really obvious but i dont see how you ended up with +2X on one side and +4X on the other.
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appu_xavier
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Poincaré Conjecture
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Andre, for some odd reason i don't think you're allowed to square both sides since it's an impossible equation. Unless, of course, you're using wrong (rong) numbers.
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Admin
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You can still square the "equation" even if it's impossible. But your job is to tell me why -3/2 is not a valid answer. My steps all valid.....except one. What was it, and why did it remove any possibility that -3/2 was the solution?


Also Noah, if you square (x + y), you get Posted Image.
Posted Image
Posted Image
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KRK
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Poincaré Conjecture
[ *  *  *  *  *  * ]
Implement -3/2 into the original problem, and you get -.5=.5
The original problem is impossible by glance so you can do anything to it you want.

You are saying x is one more than x

By the reflexive property, x=x, not x+1=x
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Admin
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I know. The problem is "flawed" to begin with. Yet, by using completely valid steps, I can turn this wrong equation into a valid one. So, show me why I can turn this equation into a valid one simply by squaring it.
Posted Image
Posted Image
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KRK
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Poincaré Conjecture
[ *  *  *  *  *  * ]
Since, you are saying x+1=x+2, and you square that, you might as well multiply both by x+1-still the same as squaring, so you get
xsquared+2x+1=xsquared+3x+2

That reduces to

x=-1

Another "solution"

When you find you can do that two different ways, the problem is automatically flawed
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Admin
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Okay, I wasn't clear enough. You are supposed to show me WHY, when you square this flawed equation, that it becomes a correct equation.
Posted Image
Posted Image
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Edwardted
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Twin Prime Conjecture
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you squared both sides. thats where the problem is.

in the left half you multiply by x+1 but on the right you multiply by x+2... u have to multiply both sides by teh same amount
You cannot win without losing.
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Admin
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Are you telling me it's illegal to square both sides of an eqaution?
Posted Image
Posted Image
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Edwardted
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Twin Prime Conjecture
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yes unless its x=x, 2=2, etc etc etc etc etc etc etc
You cannot win without losing.
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Edwardted
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Twin Prime Conjecture
[ *  *  *  *  *  *  *  * ]
Oh and also your squaring goes like this.


(x+1)^2=(x+2)^2

which is this

(x+1)(x+1)=(x+2)(x+2)

which goes against some property
You cannot win without losing.
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Admin
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No, this dosen't go against any properties (Though the original equation does...).
Posted Image
Posted Image
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KRK
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Poincaré Conjecture
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You thereby turn it INTO a legal one.
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Admin
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Yes...you're getting close....
Posted Image
Posted Image
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