Here's the question:

LetRbe the set of real numbers and letfbe the function fromRtoRdefined by

f(x) = 1/[(x^2)+1] for all x inR

Let C= {r inR|r<(1/5)}.

Find the setf^-1 (C)

From what I understand, I get:

f^-1(C)={x in R|[1/[(x^2)+1]] < (1/5)

I'm not sure if that is even close to being correct, but after I get to this point, I have no clue where to go with it.