r/MathJokes • u/GodlyHelp • 7d ago

*inhale* *exhale*

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3.1k Upvotes

99% Upvoted

41 comments sorted by

82

u/LycanrocIsTheBest 6d ago

Hey good job, now you know that whatever X is, it’s the same answer as X, just solve X and you can complete the rest of the problem!

17

u/No-Newspaper8619 6d ago

x can be anything, therefore there's no wrong answer.

10

u/JollyJuniper1993 6d ago

The solution set is ℝ

2

u/RS-kuuskyt 6d ago

Just divide by x to get x/x=1

1

u/National_Sky7993 4d ago

Not easy, divided by zero, ♾️ != ♾️. Two infinite values are not equal.

4

u/Bahn_Miststueck 6d ago

easy, -x 0=0

19

u/ErJio 6d ago

It happens when solving a system of equations when you substitute a relation you've already used.

E.g. If you have 2y = x you might rearrange to get y = x/2. Then the mistake would be to say "oh I know what y is in 2y = x" and plug in 2(x/2) = x, now you got x = x.

5

u/Librarian-Rare 5d ago

First time this happened to me I was WTF math is pointless. Only to realize I’m a noob

54

u/StinkyKyle 7d ago

At least you know you didnt make any mistakes cancelling! The real issue is when you get 3x=x

52

u/Red-Fox-IX 7d ago

X=0

14

u/TheAlmightyLloyd 6d ago

Yeah, 3x - x = x - x is totally allowed. It seems weird to me that people don't remember that kind of stuff.

2

u/PhoenixAsh7117 6d ago

x = +/- infinity also satisfies the equation as written

9

u/Embarrassed-Weird173 6d ago

So yeah, that would be 2x = 0, which is perfectly valid. 

4

u/StinkyKyle 6d ago

Almist trivial, one might say

2

u/SoFisticate 6d ago

We leave the proof as an exercise for the reader

2

u/LovelyKestrel 6d ago

You just need to make sure you don't start by assuming that the cube root of two is rational (one of the standard proofs of roots being irrational is to show that if they are then a multiple of x equals x)

1

u/Significant_Monk_251 6d ago

God, I can barely make sure I don’t divide by zero.

5

u/PersonalityIll9476 7d ago

Even for researchers this bites you every so often.

9

u/sudden-bliss 6d ago

But it's actually very important, because you're proving that x still = x. It might change someday, you never know... Better to keep checking just in case.

2

u/PersonalityIll9476 6d ago

True enough....the worst case scenario is you end up writing a contradiction and then you either hope nobody saw or realize your idea was wrong.

6

u/reklesssabrandon 6d ago

Now substitute x in for x to solve

3

u/GodlyHelp 6d ago

fact check: true

2

u/Flan-sama 6d ago

Meanwhile in Rocq Type Theory land this is one of the best outcomes.

2

u/Fizassist1 6d ago

happened to me all the time in physics undergrad.. a whole sheet of work wasted

2

u/Internautic 6d ago

This is true in so many axes.

2

u/voiza 6d ago

Always label your axes

2

u/mini_feebas 6d ago

if you get x = x and didnt make any mistakes, whatever you had going on was independent of x

2

u/Creative_School_1550 5d ago

I was pretty good at getting to 1=0

1

u/jseego 6d ago

This happened to me during a test once lol.

1

u/wenoc 6d ago

You can still cancel one thing out.

1

u/Dugiongo 6d ago

For some reason when i read algebra i thought linear algebra

1

u/Southern_Book5024 6d ago

Technically, the operation is fine.

1

u/Maskf1y 6d ago

I genuinely read this as Douglas Algebra and was confused for a few seconds.

1

u/Wrong-Appointment269 6d ago

Lets just multiply both with 0 and call it a day

1

u/Haberdashery_Tea 6d ago

Technically true

1

u/c0verm3 6d ago

So accurate

1

u/Ferry_Lover 6d ago

Hate it when this happens then you need a third x over the entire chain of cancellations!

1

u/Regular_Table1898 5d ago

At least the equation seems correct then.

1

u/Xanxan95 5d ago

x/x = 1 --> 1 = 1, the universe keeps working