Question

I need to factorise this: \[\frac{ (5n-2)! }{ (5n-4)! }\] can someone help me?

Answer 1

do you know the definition of x! ?

Answer 2

yes, i do

Answer 3

maybe:

Answer 4

use that in the numerator and you should see what to do...

Answer 5

\[\frac{ (5n-2)! }{ (5n-4)(5n-3)(5n-2)! }\]

Answer 6

but i am not sure

Answer 7

not quite

Answer 8

x! = x(x-1)(x-2)...(1)

Answer 9

so (5n-2)! = (5n-2)( (5n-2) - 1)( (5n-2) - 2)...(1)

Answer 10

oh, i see. thank you a lot!

Answer 11

yw :)