Module 8: Permutations, Combinations, and the Binomial Theorem

 

In Try This 4 you probably noticed that because n! represents the product of consecutive whole numbers, you can write a product in a variety of ways. For example, 10! can also be expressed as 10 x 9! or 10 x 9 x 8!.

 

Self-Check 4
  1. Rewrite 12! in two different forms. Answer
  2. Rewrite 7 x 6 x 5! in two different forms. Answer
Did You Know?

This is a photo of a calculator.

iStockphoto/Thinkstock

Most calculators will have a factorial key, and usually the largest calculation they can do is 69! Try inputting 69! in your calculator and then see what happens when you try to enter 70!.