1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Lim as x goes to a of sqrtx = sqrta

  1. Sep 20, 2009 #1
    this is a theorem that has a proof. in the proof they use a constant c so that epsilon is not in terms of x when you go to prove it. can someone explain this proof and also how and why you get/use a constant c to prove this theorm?
  2. jcsd
  3. Sep 20, 2009 #2
    I would have to see this proof to explain it.
    With the typical epsilon/delta proof of a limit, to prove that lim x->a f(x) = L you need to prove that for EVERY epsilon, a delta exists such that if a-delta < x < a+delta, then |f(x)-L| < epsilon.
    epsilon is arbtrary and not in terms of x or anything else, and delta will be a funtion of epsilon that you will have to choose to make |f(x)-L| small enough.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook