Register to reply

Infinite Limit Complex Function

by rmcclurk
Tags: complex, function, infinite, limit
Share this thread:
Jul1-09, 05:13 PM
P: 4
1. The problem statement, all variables and given/known data
Find the limit of a complex number involving infinity.

2. Relevant equations
Lim z->infiity of (8z^3+5z+2)

3. The attempt at a solution
I tried to split the problem into real and imaginary parts using z = x+iy, but I don't know how to deal with the z->infinity.

Phys.Org News Partner Science news on
Experts defend operational earthquake forecasting, counter critiques
EU urged to convert TV frequencies to mobile broadband
Sierra Nevada freshwater runoff could drop 26 percent by 2100
Jul1-09, 08:04 PM
P: 675
I could be misreading the problem, but the real part and imaginary part of that equation will go to infinity as well no matter which you take.
Jul1-09, 08:37 PM
Sci Advisor
HW Helper
P: 25,228
z->infinity means |z|->infinity. What can you say about lim |8z^3+5z+2|?

Jul2-09, 05:37 AM
Sci Advisor
PF Gold
P: 39,565
Infinite Limit Complex Function

Thanks, Dick. I was about to ask exactly what "z-> infinity" meant! In the complex plane there can be an infinite number of "infinities"!

Register to reply

Related Discussions
Limit of a complex function Calculus & Beyond Homework 7
Complex Variables. Complex square root function Calculus & Beyond Homework 0
Limit of sequence equal to limit of function Calculus 1
Infinite Limit Calculus & Beyond Homework 2
Limit of an infinite sum. Calculus 1