ShmoopTube

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Factorials, a la Shmoop. Hi – I’m five. Meet my friend, five factorial.

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We’re going to tell you all about factorials. WE’RE GOING TO TELL YOU ALL ABOUT FACTORIALS!

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Right. So, uh… a factorial helps you determine how to organize or arrange a large number

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of items. A FACTORIAL HELPS YOU DETERMINE HOW TO ORGANIZE

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OR ARRANGE – Whoa – why are you yelling?

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BECAUSE… THERE’S AN EXCLAMATION POINT AFTER MY NAME. IT’S KINDA MY THING.

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Ah. Of course.

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Tell you what – I’ll take it from here. SUIT YOURSELF.

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A factorial, as my friend here mentioned, ends in an exclamation point.

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However, the exclamation point – for once - is not being added for emphasis, or because

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factorials are particularly exciting. HEY!

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It is just a symbol which indicates that the number you are dealing with is, in fact, a

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factorial.

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For example, the number 4 factorial…

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…really represents: “4 times 3 times 2 times 1.”

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HOW IS THAT HELPFUL? Glad you asked.

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Say you’re going to see your favorite band Troll Slayer in concert.

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The band is great… but they’ve only written four songs:

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Deathtongue, Anvil of Evil, Scorpion Love, and Hate Shroud.

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It isn’t tough to figure out what kind of music they’re going to play…

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…but try figuring out in what order they will play their four songs.

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We know you’ve got your fingers crossed that they open with Scorpion Love.

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Then segue into Anvil of Evil, follow that puppy up with Hate Shroud, and finally bring

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the house down with Deathtongue. But that’s only one possible set list. How

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many possibilities are there?

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Well, there are 4 options for their opener.

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Once their first song has been determined, there are only 3 options for their second

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song.

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Then, only 2 options for their third…

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…and lastly, a single option left for the big finale.

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There are 4 times 3 times 2 times 1 – or 24 – possible orders for the band’s set

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list.

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Make sense? SURE! BUT WHAT IF THE AUDIENCE WANTS AN ENCORE?

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I don’t think they’re ready for that kind of math.

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GOOD CALL.

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Blurb: Do you have trouble organizing your desk?

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Are your bookshelves a disaster area? Well, you’re in luck! Act now, and get yourself

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a pack of factorials, designed to help you get your life in order! (Limit 2 per customer.)

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