# Homework Help: How to calculate the convergence point for exponential function?

1. Oct 19, 2011

### ALYAZAN

1. The problem statement, all variables and given/known data

I need to calculate the point of divergence for this exponential function :

F(x)= 5.282 * exp ( -0.01726 * x )

may you help me in finding the method to solve such problems ?

2. Relevant equations

3. The attempt at a solution

2. Oct 19, 2011

### HallsofIvy

?? In the title you say "convergence point" and in the text you say "point of divergence"? Converge as x goes to what value? If you are asking about the limit as x goes to infinity, that should be easy. "$Ae^{-bx}$" is the same as $A/e^{bx}$. No matter how small b is, as x goes to infinity, so does bx. And what happens to $e^{bx}$ as bx goes to infinity?

3. Oct 19, 2011

### ALYAZAN

I am sorry .. I meant in the thread text "Convergence" not "Divergence"

I got the point.

this function was fitting to some experimental data (Coercive force vs Temperature).

now I have another question .. which of the following functions Converges :

1- Root square function x^0.5
2- 1/x
3- x^-0.5

if they converge .. how do we calculate their convergence point ?