Beginners limit problem

1. Sep 24, 2009

synergix

1. The problem statement, all variables and given/known data
Lim sqrt(r)/(r-9)4
r->9

3. The attempt at a solution

I haven't been able to get started on this one I first tried to factor the bottom but I don't know how to or if that is even the right way to solve this problem. I am thinking maybe I have to multiply the bottom out but that seems a bit tedious.

is it sufficient to simply test from the left and right in order to get my answer?

Last edited: Sep 24, 2009
2. Sep 24, 2009

lanedance

this limit will be infinite, just by inspection

the numerator will be 3, whilst the denominator tends to 0

if you want to show it is unbounded, pick any positive number N, then show you can chose d, such that for |r-9|<d, then F(r) > N

but in answer to your question it is sufficient to show the limit is the same from the left & right