What is \[ \frac{n!}{1!(n-1)!} \]where $n$ is a positive integer?

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Lesson Parent: 
The Factorial Function
Problem: 

What is
\[
\frac{n!}{1!(n-1)!}
\]where $n$ is a positive integer?

Answer: 

\[ \frac{n!}{1!(n-1)!}=n \]

SAMPLE SOLUTION

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Solution: 

First, we know that $1!=1$ and <Sign in to see all the formulas> so we have

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