Date: 2/3/96 at 22:20:17 From: Anonymous Subject: 3! What does 3! mean? I've looked it up in my math book index about 40 times,but I'm only in fourth grade, so I might not find it there.
Date: 3/21/96 at 19:48:3 From: Doctor Ken Subject: Re: 3! Hello! 3! is a neat thing. It's said "three factorial," and it means 3 x 2 x 1. Similarly, 7! (seven factorial) means 7 x 6 x 5 x 4 x 3 x 2 x 1. And so on. Here are a couple of other things about factorials: 1! = 1, which pretty much makes sense. What's more, 0! = 1, which is really wacky. But I'm afraid it's just defined that way. Thanks for the question! -Doctor Ken, The Math Forum
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