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Mathematics 22 Online
OpenStudy (luigi0210):

Hey guys, up for proving something?

OpenStudy (luigi0210):

Prove: \[\LARGE 2+2=5\]

OpenStudy (skullpatrol):

you must have divided by 0

OpenStudy (hihi67):

http://www.youtube.com/watch?v=XXhbThOITLQ

OpenStudy (hihi67):

Watch and learn yo

OpenStudy (luigi0210):

Divide by 0?

OpenStudy (anonymous):

i think ur 1 is tryin 2 b d invisible man oops, sry..invisible number

OpenStudy (owlcoffee):

Hmm... To prove that I'll start off with something that is true: say... \[-20=-20\] rewriting them a little: \[16-36=25-45\] I'll rewrite them again: \[(2+2)^{2}-(2+2)(9)=5^{2}-(5)(9)\] if I multiply and divide by two, and reorder: \[(2+2)^{2}-(2)(2+2)(\frac{ 9 }{ 2 })=5^{2}-(2)(5)(\frac{ 9 }{ 2 })\] just playing a little with squares and fractionary statments: \[(2+2)^{2}-(2)(2+2)(\frac{ 9 }{ 2 })+(\frac{ 9 }{ 2 })^{2}=5^{2}-(2)(5)(\frac{ 9 }{ 2 })+(\frac{ 9 }{ 2 })^{2}\] Now with that, I can complete some squares: \[(2+2-\frac{ 9 }{ 2 })^{2}=(5-\frac{ 9 }{ 2 })^{2}\] by cancelative property then I can remove the 9/2 and take square roots on both sides to end with: \[2+2=5\] There is a mistake here though, try find it.

OpenStudy (anonymous):

u divided only d no 9 by 2 instead of d entire 2(2+2)(9)

OpenStudy (anonymous):

dont we have two possibilities \[2+2-\frac{9}{2}=+(5-\frac{9}{2})\] and \[2+2-\frac{9}{2}=-(5-\frac{9}{2})=-5+\frac{9}{2}\] and the combination of this equations wen added gives \[2+2=0\implies 2=0\] wich we divided and multiplied with ealier

OpenStudy (anonymous):

no its not zero its \[2(2+2)=9\implies 2+2-\frac{9}{2}=0\] meaning the 2nd last equation yields \[( 2+2-\frac{9}{2})^2=(5-\frac{9}{2})^2=0\]

OpenStudy (anonymous):

this is crazy

OpenStudy (owlcoffee):

I know, right?

OpenStudy (luigi0210):

Thank you @Owlcoffee :)

OpenStudy (luigi0210):

@Jordannyah Will this work for ya?

OpenStudy (anonymous):

the paradox is the same \[x=y\\x^2=xy\\x^2-y^2=xy-y^2\\(x+y)(x-y)=y(x-y)\\x+y=y\\x+x=y\\2x=y\implies 2=1\implies 2+3=1+3\implies 5=4\] but here its obvious the error was dividing by zero \[x-y=0\]

OpenStudy (anonymous):

the problem with @Owlcoffee proof is using the wrong implication that if\[a^2=b^2\implies a=b\]instead of \[a=\pm b\]

OpenStudy (owlcoffee):

you discovered me! :( .... *hides under rock*

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