Question : basic question about factorials

Hi

My book hasn't explained factorials very well at all. When you evaluate a factorial, do you keep subtracting 1 until the very last term is 1 so that, for example,

(2n+1)! with n = 3
2(3) + 1 x
2(3) + 1 - 1
2(3) + 1 - 2
2(3) + 1 - 3
2(3) + 1 - 4
2(3) + 1 - 5
2(3) + 1 - 6 <= this is the last term

Or do you do something else

thanks

Answer : basic question about factorials

Yes.

You can evaluate the expression in () first:

      (2n+1)! with n = 3   =   7!   =  7*6*5*4*3*2*1