Question 181096
! is factorial
which means 4! is 4*3*2*1
:
so in this problem you would be left with 
:
n+1-n which equals 1
:
so the answer is b
:
((n+1)*n*(n-1)*(n-2)...)/(n*(n-1)(n-2)....))-n
:
notice how everything from the n onward cancels so we are left with 
:
(n+1)-n