{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

ClassNotes-Math-Factorials

# ClassNotes-Math-Factorials - Sven Thommesen 2011 Math...

This preview shows pages 1–2. Sign up to view the full content.

1 © Sven Thommesen 2011 Math: Factorials, combinations, permutations (Needed in Ch 4) [Edited 09/23/08] [This note merely defines some mathematical concepts we’ll need. The chapter notes will tell you when and how to use these concepts.] In order to discuss how to calculate probability in various contexts, we need to define the following new mathematical concepts: (a) FACTORIALS The factorial is used to calculate the answer to the following question: How many different sequences, or permutations , can we form from a group of N items? Definition: the factorial N! = 1 2 3... 1 N i N i    and we define 0! = 1 For example: 2! = 2 x 1 = 2 5! = 5 x 4 x 3 x 2 x 1 = 120 For example, how many different ways can we line up 4 cars in a row? The answer is: 4! = 4 x 3 x 2 x 1 = 24 ways. To see how: for the first spot in the lineup we can pick either of the 4 different cars. For the second spot, we have only 3 left to choose from. For the third spot, there are 2 left. And for the last spot, there’s only one car left, since the other 3 have been taken. So the number of possible ways we

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern