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LOON_ATTIC · 04-29-2011 04:18 PM

fucking algebra, how does it work
[Image: R9S5p.png]

Can anyone find a flaw on this thing? I couldn't. It's when s/he takes square roots of both sides and adds 9/2 that my mind blows.
THEY'RE STILL BOTH EQUAL TO 1/4 or 0.25 WHEN CALCULATEDS, without doing shit to both sides.
But what the fuck. What s/he did wasn't illegal, you know?

Hannah-chan · 04-29-2011 06:13 PM

The mistake is when she adds 8.25 to both sides - she pulls the figure from nowhere, and it messes up the balance of the sum. The figures added should be different.

___________________ · 04-30-2011 07:51 AM

using this same math anything can equal whatever you want. Its called dividing by zero. What Dividing by zero DOES do is prove math wrong altogether, but some asshole just decided to say "LOL NUP U CUNT DU THUT"

Thought Criminal · 04-30-2011 12:08 PM

Watch on YouTube

LOON_ATTIC · 04-30-2011 12:21 PM

Dividing by zero? Different figures?
I though it was taking the square root of a negative number, after thinking about it some more. But meh.

Thought Criminal · 04-30-2011 12:30 PM

It's a mathematical fallacy. It will work with any set of numbers.

aaaaaaasd · 04-30-2011 07:27 PM

is it bad that i didn't get any of that

The Desert Fox · 05-02-2011 01:39 PM

BaronVonStrangle Wrote:is it bad that i didn't get any of that

SaintVicious · 05-02-2011 02:14 PM

http://img01.lachschon.de/images/59155_ ... od_now.jpg

xenoknight · 05-04-2011 06:22 AM

This "proof" ignores the negative roots. You must account for the negative root.

Let's test the final result though(just for fun):

2+2 = 5
2+2-5 = 0
4-5 = 0
-----------
-1 = 0
^untrue statement

aaaaaaasd · 07-12-2011 12:37 AM

[Image: sm%20wtf%20is%20this%20nerd%20shit.jpg?1306745792]

Efs · 07-12-2011 12:42 AM

The only Math I do is work out the amount of rage I feel when I go to Math class.

UnschoolShqiponjë · 07-12-2011 11:35 AM

Hannah-chan Wrote:The mistake is when she adds 8.25 to both sides - she pulls the figure from nowhere, and it messes up the balance of the sum.

This.

magikarp · 07-18-2011 02:11 PM

UnschoolShqiponjë Wrote:
Hannah-chan Wrote:The mistake is when she adds 8.25 to both sides - she pulls the figure from nowhere, and it messes up the balance of the sum.

This.

No, that part is actually valid; you can add or subtract the same number from both sides of an equation without affecting the equality.

If you imagine a very simple equation,

x = y

And then add some arbitrary value to both sides,

x + 4 = y + 4
x + (-5) = y + (-5)
x + 5/3 = y + 5/3

It's pretty clear that the equation remains true. And since you can let x and y stand for some particular values (even values represented by more complicated expressions), you can tell how it remains true in the general case.

Like other people said, the actual problem is with the step where you take the square root.

You can simplify the expression

(4 - 9/2)^2 = (5 - 9/2)^2

to

(-1/2)^2 = (1/2)^2

and that is obviously true. But since for some arbitrary value x, both x*x and -x*-x give the value x^2, to preserve the equality you have to take the absolute value of each side. So,

|(4 - 9/2)| = |(5 - 9/2)|
|-1/2| = |1/2|
1/2 = 1/2

Prince Rilian · 07-18-2011 02:43 PM

It's because square roots have two answers.

(-1)^2 = 1 and (1)^2 = 1, oh no this must mean that -1 = 1 !

Absnt · 07-18-2011 03:53 PM

Conclusions?

IllusoryDeath · 07-19-2011 05:14 AM

Absentinsomniac Wrote:Conclusions?

MATHS HURT BRAAAAAIN.

LOON_ATTIC · 07-19-2011 05:37 AM

Prince Rilian Wrote:It's because square roots have two answers.

(-1)^2 = 1 and (1)^2 = 1, oh no this must mean that -1 = 1 !

dis
Because basically thing above means that (1/2)*2 = (-(1/2))*2 (when * is a power of something).

The things that are squared are brought to be the same absolute value but one positive and the other negative after being factored.
This just brings a problem when taking square roots of shit (or quadruple, sextuple, so on) when solving/simplifying equations, I guess the thing that's being squared always has to be positive?
Hopefully not absolutely everyone's head will explode after reading this Shrug

TheHate · 07-23-2011 07:30 AM

thewake · 07-23-2011 07:35 AM

TheHate Wrote:

Algebra finally makes sense!

Prince Rilian · 07-23-2011 07:54 AM

Lunatic Wrote:
Prince Rilian Wrote:It's because square roots have two answers.

(-1)^2 = 1 and (1)^2 = 1, oh no this must mean that -1 = 1 !
dis
Because basically thing above means that (1/2)*2 = (-(1/2))*2 (when * is a power of something).

The things that are squared are brought to be the same absolute value but one positive and the other negative after being factored.
This just brings a problem when taking square roots of shit (or quadruple, sextuple, so on) when solving/simplifying equations, I guess the thing that's being squared always has to be positive?
Hopefully not absolutely everyone's head will explode after reading this

That's why when you're solving an equation with even roots, you have to put plus or minus, you have include both possibilities.

N0nLifer · 08-04-2011 03:38 PM

LOL! Now ima gonna PROLLY trol at maths sayng that 2+2=5.
Then ima gonna prove to my teacher that its true.
Btw nice vid Thought Criminal

Mather · 03-09-2015 01:04 AM

look it's pretty simple sqrt(x^2) is not equal to x but equal to |x| therefore when he put sqrt passing from step 3 -> 4 he forgot the ||

Chanku · 03-11-2015 06:42 AM

Mather...why did you even bump this thread? Please look at the date of the last post before posting...

schoolsux · 03-13-2015 11:37 AM

How the fuck???

Missile · 03-13-2015 11:42 AM

Everytime I see one of these old threads with a bunch of posts from inactive users, I imagine myself in a graveyard

Threaded Mode \| Linear Mode What is this I don't even - Algebraic "proof" that 2+2=5
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