TikTok is a bad math goldmine! Solving x+2=x-2. Reddit r/sciencememes 

You wasted your time with this video.

If you apply limits and assume x is going to negative or positive infinity you get an answer.

*Reddit* isn't any better.

@@ToguMrewuku Hi #bot

​@@Real-Name..Maqavoy at least reddit has downvotes and a place for math, so people know if they're wrong

Yes, I can.

This stupid comment has more likes than the comment below this, which has actual valuable information unlike this junk

(X+4) does not equal x

Who came up with it was for sure just writing down random numbers, the statement "a number plus two is equal itself minus two" is a paradox

​@@devookoWell not exactly that because it is still working out something, you can just read it and say no soln exists, because the statement essentially says that find x such that increasing x by 2 is the same as decreasing x by 2, which is not possible. So no solution.

Nuh uh

"Time of day" + 12 hours = "Time of day" - 12 hours

​@@khaitomretro you missed a (mod 24) at the end

​@@kebien6020 "x+2 = x-2... in ℤ₄; I'm fine!"

​@@khaitomretro no. That cannot be used to solve this problem.

That's how you can tell that this is almost certainly someone yanking our chain. Most of the algebra is just to distract attention from the blatantly ridiculous first step.

Bros probably solve the 1st line, then ask chatgpt to solve the rest 💀

What he is showing first is the solution from the TikTok video. Then he proceeds to show how it is wrong.

@@cybore213 OC wasn't talking about bprp

@pegasoltaeclair0611 Thanks. Sometimes it's hard to figure out who the comment refers to. But I should have figured out that the OP was referring to the guy who posted the TikTok answer.

Computer science square root of -1... because computers don't work without "I"

well its an assignment operator, not checking for equal. Checkng for equal is ==.

@@user-vs1mn8ig8wwoosh

@@user-vs1mn8ig8wThat’s part of the joke bro

That's becausewe don't have proper notation for iterable variables. In computers x = x + 1 means. (new/next x) = (current/previous x) + 1

-remembers the negative square root -doesnt realise a number minus two would never be equal to the same number plus two

​@@kraquinette2430 unless the numbers are mod 4. Then x=2 would satisfy it.

@@bobbobert9379 Sure, but then you'd expect that to be explicitly mentioned.

I mean they literally could’ve just checked it, there is no way 2+2 = 2-2 (if you use sqrt4 which idk why they didn’t even simplify it down to just 2 but I digress)

There's nothing wrong with the way they've written it because √ is always positive.

I think the thing is that -2+2=2-2.

​@@error_6o6but you're saying x=-2=2

Quadratics can have multiple solutions, x=2, x=-2 indicates that x could be either, and not that it is both

The average tiktokers knowledge of math:

it’s probably a 12 year old who was just really eager to use the new identity he learnt

@LumiaFenrir-nn2pz and you’d be surprised by the number of Asian fetuses that know how to solve quadratic equations in microseconds

but it doesn't even imply x = +-2. When you say "x = +-2" that means x is either 2 on both sides of the equality, or -2 on both sides of the equality. You can't mix that precisely because it's an equality. When you solve a quadratic formula you also end up with "all x in the formula are either x1 or x2", but you never have one x being x1 and another being x2 at the same time.

@@user-uz4vr7to8c Not sure what you mean by "on both sides of the equality" here. x is only on one side of the equality. When I said "x=±2", I was shorthanding, "either x=2 or x=-2."

😂

I was looking for comment like this. I got micro aneurysm just by looking at it: x+2=x-2 ==> (x+2)(x-2)=0, followed by second step. Yea maybe in some imaginary cosmos where law of mathematics and physics don't exist created by TikTok's influencers.

Meth is herd

​@@Mike_B-137 TikTok managed to combine additive and multiplicative rules together. Because if you divided one side to the other, the other side would be one. If you multiplied, it would be (x-2)(x+2) but the other side would be (x+2)^2. Not 0. Also, if you subtract the one side, you would get zero, but, the other side would = 4. Which, that is one way to find no solutions just like subtracting just the x on both sides. The problem is they multipled on the left side, but, subtracted everything on the right. And broke Algebra rules. So, they applied multiplication to the left side and then assumed the right side would cancel to 0. Remembering some of Algebra but forgot you have to subtract. And then after that incredibly wrong step, it just gets stranger and more wrong. Lol. Gosh. I think the comment may possibly be a troll. Lol. To mess with TikTok, but, not 100%. Could be someone overconfident in their Math abilities. Either way, they seem to have just kept working until they found a solution somehow. And each step seems reasonable to someone untrained in Math, but, to someone who is trained in Math, it is obviously wrong and insane each step of the way to a misshapen "solution".

I saw some tiktok coders through other platforms and it was down bad, but this is too much, how come as a society we need to explain x+a = x-a if a /= 0 is wrong. System has failed.

How did you do that?

@@blacklight683 there is no sol.

No, he simply copied what tiktok gave as the answer and then explained why it is complete bullcrap. The tiktok was a joke, literally.

@@Kyrelel talking about the commenter, not the guy explaining

@@KyrelelWe say “Once TikTok was launched, parents’ nurture f**ked up” (It’s Chinese, I try to translate it, but it still mean TikTok mess up everything)

I'm acting like that wouldn't happen to me, but it happened even on tests (the worst part is that I'm a physics undergrad 😅)

Surely, The equation x + 2 = x - 2 should be replaced with x + 2 ≠ x - 2

another solution is changing = to > x+2=x-2 (false) x+2>x-2 (true)

Another solution, the equation is in Z/2Z

I love this comment. 😂

​@@wqrwtrue dat.

It's a love-hate relationship

I love Math = I love Math

Bro got a degree in psychology but failed math 💀

Ахуеть, я только что узнал, что у слова "фигня" есть английский аналог.

​@@Бобреккакойтане пиши сюда больше никогда

Lol yea most people just nope out seeing square roots even though this one is quite simple. But that means they won't catch how the answer doesn't even work if you plug them in which is checking your work 101

​@@Бобреккакойта garbage - мусор

😂

One day he shall no longer have a need for markers, his mind is enough

The real answer is not in finding x. The real answer is that this addition is defined over ring of remainders of division by 4. In which 2 = -2 since 2+2 = 0. Therefore, the equation is true for any x. We are threading in the realms of abstract algebra, where everything is possible.

Lmao! 😂😅

He edited it out

Even worse, this was obviously multiplying both sides with (x-2).

That was not dividing both sides. That was multiplying the left side by (x-2) while SUBTRACTING (x-2) from the right side to give that zero. What was done as the first step is this : (x+2) = (x-2) → (x+2)*(x-2) = (x-2) - (x-2) → (x+2)(x-2) = 0

@@KualinarNono, it was just dividing both sides by 1/(x-2). I don’t know what composition rules they’re working under where that equals 0 on the right hand side, but technically it was dividing both sides by 1/… just as much as it was multiplying by (x-2)

@@Tristanlj-555 Dividing can never reduce a value to zero. ONLY a subtraction can do that. Then, a division by (x-2) would have made the left side into THIS : (x+2)/(x-2) NOT (x+2)*(x-2)

@@Kualinar I know that. I just finished my last exam, complex analysis for my first year of mathematics at Uni. I alluded to that jokingly by mentioning composition rules.

You'll run into a problem here, the solution they got is x = 2 or -2. If you plug in -2 on the left and 2 on the right it technically works. Obviously you're supposed to do the same number for both x values but we're past the point of them doing the right thing.

@@jacobisbell9388 Yeah to be fair that makes sense.

​@@jacobisbell9388yea but even just looking at the equation, how would x plus n be equal to x minus n. no calculations needed.

​@@Tealen Unless n is 0, which it is not.

@@Pingwn yes, in this case its 2. I should have mentioned it

Thanks!!

I got it from Amazon haha

​@@adityagoyal7110 0-2=-2 0+2=2 -2=2 So no, its not correct

​@@adityagoyal7110 aah yes 0 - 2 = 0+2 which would imply or -2 = 2

​@@adityagoyal7110 Since when adding or subtracting to 0 gives back 0? Are you implying 0 is infinite?

Meth

Fr, I can't even follow the thought process, i'm so confused

It was revealed to me in a dream

Isn't it supossed to be x+2=x-2 x-x=2+2 0x=4 meaning it has no solution?

​@@Trap-chan750 little mistake, you forgot the - on the first two, meaning 0x = 0

I am sure that if you would stop at 0X=-4, someone would say X = -4/0

​@@tundcwe123i mean now that you mention it..... infinity + 2 = infinity - 2. That is if you consider dividing by zero to equal infinity, and not undefined

​@@xanderlastname3281infinity is not a number. Can't work with it like that outside of a limit or other special conditions.

@@Artleksandr ok but it's a concept If you have infinitely many things (natural numbers), and you simply append 2 numbers (0 and -1) you still have infinitely many numbers Cardinality hasn't changed If you them subsequently remove -1 and 0, you still have infinitely many numbers Sure it's not a "number number" like 5 or 87, but the concept still works Adding or removing finite elements from an infinite set does not change the cardinality of the set nor the number of elements

you can just plot the (x+2)/(x-2) hyperbole and the asymtotes are obvi x=2 and y=1, so it will only (almost) converge at both positive and negative infinity.

The two statements have the same slope (1) if you look at them as a function of x, but have different y-intercepts (2 and -2). So they are parallel on the same plane, thus never intersect. If you solve you get 0=4 or 0=-4.

My teacher also hated ‘cancel’ for the same reason. There’s no need to invoke any magic!

​@@rezwhapDoes that also apply to Twitter?

I'm sure if the original presenter of this problem and solution had done the check, he would have plugged in the negative value that he obtained on the left side, the positive value on the right, and shown that indeed his solutions work!

Plus or minus infinity also works as a solution btw

Just in case this isn't a meme, infinity isn't a number. You can never have x equals infinity, only x aproaches infinity or lim x = inf. There's a reason why R = (-inf, inf) and not [-inf, inf]

I mean only the first step really is

Integers mod 2 has infinite solutions :)

@@liamernst9626 That is an *excellent* answer! I wish I had thought of it. Of course, modulo 4 also works and has the advantage that "2" is still called 2 in that system.

​@@rorydaulton6858🤔 this is essentially a question of whether two parallel lines can intersect at one point

​@@vdm942no

​@@vdm942 Agreed.

Happy birthday

Or negative infinity -♾️

Tried but couldn’t solve it. I’d love a video on this problem

(a^2 + b^2 + c^2) is below the first three equations and on the right side of 'Find:'. Thanks me later.

There's probably a better approach but you could solve it by brute force. I suggest substituting √a, √b and √c by u, v, and w just to get rid of the square roots. You'll then get this system of equations: u + uv + uvw = 12 v + vw + uvw = 21 w + uw + uvw = 30 Three equations with three variables should yield solutions. Then, plug the solutions into the last term. (Just remember that it will have to be u⁴ + v⁴ + w⁴.) I had WolframAlpha do the work for me. There are three sets of solutions. the sum of squares that we are supposed to find can be either 2433, 10002, or 312688557441/384160000. Like I said, maybe there's a better way but the old-fashioned way should work. If I had to do it by hand, I'd start by subtracting the second from the first equation: u + uv - v - vw = -9 We can isolate u by factoring it out and bringing the other stuff on the right hand side: u (1+v) - (v+vw) = -9 u = (v+vw+9) / (v+1)

it took me some time and I must have made a mistake in my regular scholarly attempts, but then it jumped at me: it works for a = 1, b = 1, c = 100, so your result is 10002. method: first substitution for those ugly sqrts: A = sqrt(a), B = sqrt(b), C = sqrt(c), so you get A + AB + ABC = 12 B + BC + ABC = 21 C + AC + ABC = 30 now you see every next equation is 9 bigger, so it is as if you subtract 1 and add 10. and this really works if A = 1, B = 1, C = 10 so you get 1 + 1 + 10 = 12 1 + 10 + 10 = 21 10 + 10 + 10 = 30 A^4 + B^4 + C^4 = 1 + 1 + 10000 = 10002

@@popularmisconception1 Thank you, I liked your idea, but you found the answer by guessing.. Can we solve it by mathematical steps?

Exactly. And -infinity as well.

​@@vasiliynkudryavtsev True. Well spotted. 😊

Tis not how infinity works

@@treeNash Ah, yes, and neither is it how infinity DOESN'T work.🙃

Solutions are x=+infinity or x=-infinity

@@dannyyeung8237 infinity is not a number so you cannot even say x=inf. you can only say something like x approaches infinity, never equal

What? Your second step is wrong, Mr. TikTok

that's an interesting approach, too bad infinity is not actually a number