SOLUTION: I need help with limits and cant find a section... Find the following limit: lim (x^2+2x-15)/(x-3) x->3 I think the limit might be 7, but really unsure. Thank you!!

Algebra ->  Square-cubic-other-roots -> SOLUTION: I need help with limits and cant find a section... Find the following limit: lim (x^2+2x-15)/(x-3) x->3 I think the limit might be 7, but really unsure. Thank you!!      Log On


   

Question 436687: I need help with limits and cant find a section...
Find the following limit:
lim (x^2+2x-15)/(x-3)
x->3

I think the limit might be 7, but really unsure. Thank you!!
Found 2 solutions by stanbon, richard1234:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
I need help with limits and cant find a section...
Find the following limit:
lim (x^2+2x-15)/(x-3)
x-->3
===============================
Factor:
limit{[(x+5)(x-3)]/(x-3)}
x--->3
===============================
=
limit[(x+5)] = 8
==============================
Cheers,
Stan H.
x--->3
=================

Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
You can definitely factor the numerator as the other tutor did. In cases where the numerator does not factor (i.e. the general case) you would use L'Hopital's rule:

(take d/dx of top and bottom, evaluate the limit).