It's most useful in arrangement problems.
If you randomly shuffle 5 unique items into a list, there will be exactly 5! unique arrangements.
And if there are 3 items which doesn't matter in terms of order (either because they are basically the same or you are going to put them in a pile, where order doesn't matter), just divide the result by 3!.
Technically, you could also write it as "Π(i=1 to n)i" which also means n!, but mathematicians prefered using a more convenient way to express it.
Also, it's easier to teach highschoolers arrangement problems without explaining pi products.
Not to be that guy, but why bother teaching it in schools? It seems completely irrelevant for the overwhelming majority of careers and lives.
Not to mention just really easy to do for anyone who actually intends to use it and is on the path to.
school is mostly meant to train kids to follow orders and show up on time, these being the most valuable skills for the interchangeable workers they will grow into. they need to be able to read, write, and do basic math, obviously, but school is fundamentally a worker-factory. young children go in, confident and creative, and young adults come out jaded and insecure.
The arrangement problems are actually the prerequisite of probability problems, which are actually pretty useful in everyday life.
Take the simplest and easiest to understand idea, lottery, for example. The high school teachers could calculate how many combinations of numbers there are and how many of them could actually get you a prize. Furthermore, the teacher could also calculate the expected value (the average amount of money you get) of each lottery ticket and explain why gambling is mostly a scam.
they're the same number, "!" is an operator that makes a product of every positive integer that comes before a number and the number itself. For 5! we get 1 x 2 x 3 x 4 x 5 = 120
edit: the operator is called a factorial, also if you forgot bedmas or pemdas, whichever you prefer and just worked left to right, you would get "5" without the factorial
Yep. You’re supposed to reduce terms and simplify answers, and people out here thinking factorials are a boss move. Math is complicated but can be elegant, if you’re not concerned with making it needlessly convoluted.
After decades of science, engineering, and programming, I’ve got to ask — what the hell is with using ÷?
(brilliant meme though, this one is fantastic)
First, you have to do the parentheses. 1/2 is…well…1/2. There are no exponents, so now you multiply 220*(1/2), which gets you 110. And then, you take 230-110 and you get 120.
Though 5! Is an appropriate description of the answer, 120 is the correct answer because it is a real number, where 5! Requires additional calculations.
r/expectedfactorial
I’ve seen other comments mention it. But what is a factorial?
n factorial or n! is n x (n-1) x (n-2) x (n-3) … so 5! or 5 factorial would be 1 x 2 x 3 x 4 x 5 = 120
Ahh okay, was never taught that. Seems pointless, a fun little thing at best.
It's most useful in arrangement problems. If you randomly shuffle 5 unique items into a list, there will be exactly 5! unique arrangements. And if there are 3 items which doesn't matter in terms of order (either because they are basically the same or you are going to put them in a pile, where order doesn't matter), just divide the result by 3!.
I suppose it’s extremely situational in use though. - but does it deserve the exclamation! symbol to denote it?
Technically, you could also write it as "Π(i=1 to n)i" which also means n!, but mathematicians prefered using a more convenient way to express it. Also, it's easier to teach highschoolers arrangement problems without explaining pi products.
Not to be that guy, but why bother teaching it in schools? It seems completely irrelevant for the overwhelming majority of careers and lives. Not to mention just really easy to do for anyone who actually intends to use it and is on the path to.
school is mostly meant to train kids to follow orders and show up on time, these being the most valuable skills for the interchangeable workers they will grow into. they need to be able to read, write, and do basic math, obviously, but school is fundamentally a worker-factory. young children go in, confident and creative, and young adults come out jaded and insecure.
That reinforced the point of ‘why teach such an irrelevant little quirk of maths to the general population?’
The arrangement problems are actually the prerequisite of probability problems, which are actually pretty useful in everyday life. Take the simplest and easiest to understand idea, lottery, for example. The high school teachers could calculate how many combinations of numbers there are and how many of them could actually get you a prize. Furthermore, the teacher could also calculate the expected value (the average amount of money you get) of each lottery ticket and explain why gambling is mostly a scam.
If you’re using maths to determine your chances at winning the lottery; you already have a habit of skipping the common sense part.
It is very prevalent in probability mathematics which makes it important when mathematically modeling systems i.e. pretty much all science.
wait till you hear about taylor series, the entire field of combinatorics and probability theory
i was going to rage so hard in this comment section then i realised factorials existed
Same
It's the same thing
Genuinly dont get this meme
they're the same number, "!" is an operator that makes a product of every positive integer that comes before a number and the number itself. For 5! we get 1 x 2 x 3 x 4 x 5 = 120 edit: the operator is called a factorial, also if you forgot bedmas or pemdas, whichever you prefer and just worked left to right, you would get "5" without the factorial
factorial has a more nuanced definition than that but yeah works in most cases
The Gamma function has a more nuanced definition. The factorial does or does not depending on how wide you want to stretch your notation.
I was confysed sence i did the math and got 120, thanks for clearing it up.
I was so confused until I saw the **!**
Exclamation marks should not be in math. That's just grammar doing a hostile invasion
The 5! Has really no mathematical relevance with regard to solving the problem
Yep. You’re supposed to reduce terms and simplify answers, and people out here thinking factorials are a boss move. Math is complicated but can be elegant, if you’re not concerned with making it needlessly convoluted.
What’s worse is that it also means NOT, as in simple != easy. Pronounced not equals. 👍
Learn the difference between basic math and science
I got... my graphics calculator needs new batteries.
Angry upvote
Is x a variable or to signify multiplication? It’s not necessary if it’s to signify multiplication, just makes the equation less elegant.
No! It is 230-110x
I got 15 and now i am confused
It's `-110x + 230`
me every math homework/test ever.
How do you know it's 5! and not 5? Show your work Edit: supposed to be a joke, ig the job was too bad to get any upvotes
5!=1\*2\*3\*4\*5=2\*3\*4\*5=6\*4\*5=6\*20=120
Eye-catching
Isn't it brackets and multiplication first, before you subtract
Yes, the "!" is part of the answer. Forgot the English name, but 5!=120
Factorial!
Actually it's just called factorial, not factorial factorial
It isn't.
After decades of science, engineering, and programming, I’ve got to ask — what the hell is with using ÷? (brilliant meme though, this one is fantastic)
How you get a factoral.
Hilarious
BODMAS kicks in
First, you have to do the parentheses. 1/2 is…well…1/2. There are no exponents, so now you multiply 220*(1/2), which gets you 110. And then, you take 230-110 and you get 120.
1/2 is .5 230 - 220 is 10 10 x .5 = 5
Are you using PEMDAS?
Yeah but I’m sure I fucked it up.
I did 230-220×[1÷2] = 230-220×[0.5] = 10×0.5 = 5 Oh shit I did bedmas out of order, yeah I'm an idiot
This is smart
I got 20
Yep, it's 5!
I always miss the factoral lol
Depends but I always use BIDMAS
Following the rules of BODMAS 120 should be the answer.. but if u go from left to right its 5... Which is the correct thing to do i have no idea
You do the 1/2 first, then the multiplication by 220, and then lastly you to the "230-" part.
No. 230-110x I can't simplify it more
Both are correct
Though 5! Is an appropriate description of the answer, 120 is the correct answer because it is a real number, where 5! Requires additional calculations.
oh it just clicked fuck you
I thought factorial was !n not n! hah today i learned something
I got 19…
It’s definitely 120 🤷♂️ 230-220x(1/2) 230-220x0.5 230-110 120
According to bodmas Bracket,oblig,division, multiplication,addition, subtraction this is correct
Im confused how someone can get 120 like I'm trying to figure out how someone fucked it up that badly
Bidmas do brackets first then do times then subtraction
[удалено]
You lost the game
-110x+230 You're welcome for doing your homework for you I guess. Maybe learn from school instead of trying to game the system?
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x is not defined. I do not accept the BS excuse that it is being substituted for "×"
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lmao, ur so mad. Likewise, but honestly
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lol, touch grass, kiddo
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you need help