Question

How do I divided factorials ?

Answer 1

Answer:

Unfortunately factorials aren't the prettiest to divide but there are some tricks to help make it easier.

It's probably easiest to explain with an example.

Say we wanted to find the answer to $\frac{6!}{4!}$

Well we know that we can rewrite this as $\frac{6 \times 5 \times 4 \times 3 \times 2 \times 1}{4 \times 3 \times 2 \times 1}$

So we can cancel out the $4 \times 3 \times 2 \times 1$ from the numerator and denominator.

This leaves us with $6 \times 5 = 30$ which is much easier than what we had before.

So I guess if you are dividing factorials, try to expand them and try to find parts that cancel out.

Hope this helps!