@jaytee12003,
Engineer is completely correct.
if f(x)=2x+1
then y=2x+1->2x=y-1->x=(y-1)/2
now substitute x for y
so the inverse f^-1(x)=(x-1)/2
but now check your answer with the property
f o f^-1= f^-1 o f=x
((2x+1)-1)/2=2x/2=x & 2((x-1)/2)+1=(2x-2)/2+1=x-1+1=x
So the inverse is f^-1(x)=(x-1)/2
the rules for finding an inverse of a one to one function are
1) substitute y for f(x)
2) solve for x in terms of y
3) then substitute x for y
4) check your answer
Rap