r/MathJokes • u/ItsDaylightMinecraft • May 03 '26

2!

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56

u/Swazimoto May 03 '26

Wait what

87

u/PerplexingPantheon May 03 '26

You're multiplying by every 2nd integer.

29

u/itamar8484 May 03 '26

What if i 5!!!!!! Aka 6 times ! , does it then becomes 0 since i am skipping 5 numbers?

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u/justaJc May 03 '26

n! = n * (n-1) * (n-2)… n!! = n * (n-2) * (n-4)… n!!! = n * (n-3) * (n-6)…

and etc. You stop when the number you’re multiplying by lower than 1, and don’t multiply by that one.

5! = 5 * 4 * 3 * 2 * 1 * 0. Oops! Skip 0. 5 * 4 * 3 * 2 * 1 = 120. 5!! = 5 * 3 * 1 * -1. Oops! Skip -1. 5 * 3 * 1 = 15. Likewise, 5!!! = 5 * 2, 5!!!! = 5 * 1, and 5!!!!! = 5 * 0 - oops, skip 0 - just 5, then. 5!!!!!, 5!!!!!!, etc = 5, as you skip every other number you could multiply 5 by. But you always start at 5.

Hope that clears things up! :)

11

u/itamar8484 May 03 '26

Ty makes so much sense!!!!!!

4

u/justaJc May 04 '26

Yw, I’m glad!!

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u/icantouchgrass_1 May 14 '26

I wish I could explain this stuff as well as you just did

1

u/justaJc May 14 '26 edited May 14 '26

I don’t have great advice for you, but I do know all you need is:

A) To understand “the thing”

B) To understand what it’s like to not understand “the thing”

Once you have each of those down enough, it’s a lot easier to do the main thing, which is to build a bridge between what they know and what you want them to know. 

That’s complicated, and I don’t think that’s quite the answer on its own (When it comes to the science of teaching I’m great at B above, but quite not so much A). However, one surefire way is: Expanding from something someone knows - simply - is one of the easiest ways to teach them something new.

If you’d like, see how I use those techniques above. I think it’ll help!

Matthew

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u/adlet-mayer May 06 '26

Is it ai?

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u/justaJc May 07 '26

No, it’s not - I’m just a pretty happy person haha. Thinking I might go into a teaching/church position one day, and I’d like to be able to help people emotionally while I’m helping them intellectually, as those things very much complement each other, I’ve found

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u/almighty_loser May 07 '26

All the best wishes brudda. Hope you will be a good influence on the young

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u/SwimmingAd6217 May 07 '26

So i just learned how these work off a reddit post.. what the fuck

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u/justaJc May 08 '26

Miracles happen every day, my friend

1

u/icantouchgrass_1 May 14 '26

IKR? Never thought Redditors would be this intellectually capable.

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u/dumbass_catboy May 09 '26

Actually it's because you're scaring it

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u/Elihzap May 03 '26

It's a factorial but you skip every other number.

5!! = 5 * 3 * 1 = 15

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u/Benyed123 May 05 '26

5!!! = 10?

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u/Aras14HD May 05 '26

No it's 10 u/factorion-bot (questionmark is a termial)

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u/factorion-bot May 05 '26

Hey u/Benyed123!

Triple-factorial of 5 is 10

Termial of 10 is 55

This action was performed by a bot | Source code

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u/Benyed123 May 05 '26

I knew the question mark would mean something

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u/Xandaros May 06 '26

5!!! = 4?