hi,

I'm trying to do a proof by induction showing that (2x+1)!/(2^x (x)!) = ((2x+1)(2x-1)!)/(2^(x-1) (x-1)!) , but i don't quite remember factorial manipulation. I can recall that (x+1)! = (x+1)x! , but i can't remember if there's anything like this for (x-1)! or in this case, (2x-1)! as well.

any help is appreciated!