Hi,(adsbygoogle = window.adsbygoogle || []).push({});

I have a question about factorials that I'm hoping someone can help me with.

I know that the factorial n! means the product of the integers from 1 to n, for example if I have 4! then this is equal to 4 x 3 x 2 x 1 = 24, but I have an equation which contains the term:

k(n-1)!

I am not sure how to interpret this...for instance, if we assume that k=4 and n=8, does this give:

4(8-1)!

= 4 x 7!

= 4 x 5,040

= 20,160

Or does it give:

4(8-1)!

=4 x 7!

=28!

=3.0489 x 10^29

I'm guessing it's the first one but am not sure...can someone confirm or provide the correct answer please?

Many Thanks

-Rob

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Factorial Question

**Physics Forums | Science Articles, Homework Help, Discussion**