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!

Homework Help: A problem in limit of a complex function

  1. Apr 12, 2012 #1
    1. The problem statement, all variables and given/known data
    I'm a newbie at complex analysis.

    lim [itex]\frac{\bar{z}^{2}}{z}[/itex]

    2. The attempt at a solution
    L'Hospital rule gives the answer in no time. But how do you solve without it?
  2. jcsd
  3. Apr 12, 2012 #2
    Well, I think it would help if you read up on how to do limits in complex analysis first.

    You basically have to find out the limit as x->0 and y->0. You have to do it twice.

    For e.g. as x->0 and then y->0 (1) -- then y->0 and then x->0 (2), this way you might find there are two different limits; this means the limit does not exist.
  4. Apr 12, 2012 #3
    But the answer is zero.

    Also can you suggest me some good self-study material to learn complex calculus? I'm good at real number calculus, and I started reading this book called 'Complex Variables Demystified' by David McMohan. But it's the only one I have.
  5. Apr 12, 2012 #4

    Yes, well when you calculate this limit you will find out it is zero. It matches.

    I'm sure some more experienced users can suggest much better material. I too am fairly new to this stuff. There are plenty of online notes, books, etc though.
  6. Apr 12, 2012 #5
    Thanks a lot.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook