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Petrus
grak
Feardotpew
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Feardotpew

Feardotpew


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Join date : 2008-09-22

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PostSubject: @ Algebra   @ Algebra I_icon_minitimeThu Feb 05, 2009 10:47 am

So I found this. It made me think. My conclusion is that everything I have ever known and loved is wrong. Discuss.

@ Algebra 12338510
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grak

grak


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeThu Feb 05, 2009 11:01 am

divide by zero troll divided by zero
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Feardotpew

Feardotpew


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeThu Feb 05, 2009 11:06 am

...I see no 0's in previously stated equation.
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grak

grak


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeThu Feb 05, 2009 11:14 am

If A=B, then A-B=0.

The factored line then becomes: (A-B)(A+B) = B(A-B) --> 0*(A+B) = 0*B

It does not matter what you multiply 0 by. The result is still 0 on both sides. You are not allowed to divide by zero (which is what A-B is since you defined A=B) because the result is undefined.
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Feardotpew

Feardotpew


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeThu Feb 05, 2009 11:27 am

So math is fun. Scuse me while I stab myself in the leg repeatedly.
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Petrus

Petrus


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeThu Feb 05, 2009 11:28 am

They did not specify values for A and B at the beginning. The purpose must be to find what A and B are, and in the case listed at the end the answer can only be zero, which means the whole thing doesn't work.

Also, I was always a fan of 2+2=5 because 2.4 + 2.4 = 4.8, which is just as ridiculous.
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Feardotpew

Feardotpew


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeThu Feb 05, 2009 11:30 am

I do believe Grakk has won.
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Petrus

Petrus


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeThu Feb 05, 2009 11:35 am

I think Grakk needs to go show that to Mrs. Grakk before she does her next round of math homework.
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grak

grak


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeThu Feb 05, 2009 11:40 am

Quote :
The purpose must be to find what A and B are, and in the case listed at the end the answer can only be zero, which means the whole thing doesn't work.

Not necessarily. A=B was just provided as a starting assumption. Deriving a relationship that depends on that assumption doesn't mean you have to solve for A and/or B, given other assumptions. But as they say, "You can't get there from here." In every step, the problem is a modification of an identity because there is no information contained in the starting statement.
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Feardotpew

Feardotpew


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeThu Feb 05, 2009 12:50 pm

You know, I can almost understand why Mrs. Grakk got upset when you were trying to teach her math.
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grak

grak


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeThu Feb 05, 2009 1:06 pm

I get frustrated with my wife when she works on math because she wants to use some kind of head trick, short cut, or mnemonic to move on to the next problem instead of understanding how to work the problem. I can't really blame her for it because her education sucked due to her parents being uneducated and not giving a shit about her. But there it is anyway. I also suspect her teachers at the community college are (with rare exceptions) the same kind of student farmers that characterize high school teachers. Cram em through and fuck all if they learn anything. So after she gets her head filled with mnemonics and short cuts, she comes home and gets the real story from me and gets annoyed that it doesn't match what her automaton of an underpaid instructor tells her.

If you understand the concept, I don't have to come downstairs every fucking 5 minutes. You probably think I sound like an old fart for saying it, but getting to the answer is not the point. You can learn to apply what you learn in the real world by understanding the problem. Getting the right answer does you no lasting good.

Not bitter or anything...no no.
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BaronVardus

BaronVardus


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeThu Feb 05, 2009 1:09 pm

Feardotpew wrote:
So I found this. It made me think. My conclusion is that everything I have ever known and loved is wrong. Discuss.

@ Algebra 12338510

@ Algebra Wts
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Feardotpew

Feardotpew


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeThu Feb 05, 2009 2:45 pm

I had a whole mindfuck thing going on by reading that, but Grak kinda ruined it for me with his analytical skills.
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Necis
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Necis


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeThu Feb 05, 2009 4:26 pm

Grakk you may be my new hero (mathematically speaking) because getting the right answer is no where near as important as understanding the process.
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Feardotpew

Feardotpew


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeSat Feb 07, 2009 12:48 am

@ Algebra 12339810

Grakaru. Discuss
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Peanutbutter

Peanutbutter


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeSat Feb 07, 2009 3:31 am

Feardotpew wrote:
@ Algebra 12339810

Grakaru. Discuss

(3-4)^2 = (5-4)^2
+/-(3-4) = +/-(5-4)
+/- 1 = +/- 1

qed
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Petrus

Petrus


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeSat Feb 07, 2009 3:32 am

That is so incredibly stupid I don't know how it got anywhere. 3-4 = -1 and 5-4 = 1.

Here's what that picture says:

9 - 24 = 25 - 40 (True, both are -15)
9 - 24 + 16 = 25 - 40 + 16 (True, both are 1, as it's -15 + 16 = 1)
(3 - 4)^2 = (5 - 4)^2 (This is also true, though I don't understand how they got to this step)
3 - 4 = 5 - 4 (Completely wrong. The square root of (3 - 4)^2 is not (3 - 4). It is 1. Whoever wrote this should be sent back to 6th grade.)
3 = 5 (The last step was a giant fallacy, and adding four to both sides doesn't make it better at all. Morons should be kept away from math.)

edit: pb beat me to it, qq
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Peanutbutter

Peanutbutter


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeSat Feb 07, 2009 3:40 am

Actually Petrus, you can take the sqrt of both sides like that and keep it "expanded" (imagine both values were variables), but you must remember that a sqrt is always plus or minus. You can't just assume it's the positive version.
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Kamma

Kamma


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeSat Feb 07, 2009 6:38 am

If you guys want to chase your tail for a bit over something trivial, go read about clopen sets.
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grak

grak


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeSat Feb 07, 2009 10:18 am

Math: it works, bitches!
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Feardotpew

Feardotpew


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PostSubject: Re: @ Algebra   @ Algebra I_icon_minitimeSat Feb 07, 2009 2:33 pm

Well PB already explained what I was going to explain to you Petrus, so I'll just leave it with this thought.

I took both my cats to the vet today. The vet is located practically right under an above-ground train line. My cat is terrified of the noise it makes. TERRIFIED. To the point where he'd flip the fuck out inside his cage, spin around a bit, move the towel from under his feet and hide under it, like a security blanket. I lold.
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