How do you simplify (2k)!/(2k+2)! to 1/(2(k+1)(2k+1)) ?

1 Answer
Feb 6, 2018

The expression we want to simplify is

E = ((2k)!)/((2k+2)!).

Since (2k+2)! = (2k+2)(2k+1)(2k)!, then:

E = ((2k)!)/((2k+2)(2k+1)(2k)!).

Then:

E = cancel((2k)!)/((2k+2)(2k+1)cancel(2k)!).

This gives

E = 1/((2k+2)(2k+1)).

We can rewrite (2k+2) = 2(k+1); then:

E = 1/(2(k+1)(2k+1)).

Hope it helped!