Question

What is the value of $n!$ by formula?

Answer 1

Find the value of $n!$ by formula.

A factorial function multiplies a number by each successive number below it.

$n!=n\times \left(n-1\right)\times \left(n-2\right)...3\times 2\times 1$

Also, the product of the number $n$ and the factorial of that $n-1$ is the recurrence relation for the factorial of a number.

Therefore, $n!=n\times (n-1)!$

Hence, the formula for $n!$ is $n\times (n-1)!$.