Power series when variable is very large

In summary, power series are mathematical expressions that involve a variable raised to increasing powers. When the variable becomes very large, the series can be approximated using specific formulas, such as the Binomial series or the Taylor series. These approximations are useful in solving complex problems in fields such as physics and engineering. However, as the variable approaches infinity, the accuracy of the approximation decreases and the series may even diverge. Therefore, it is important to carefully consider the range of the variable when using power series.
  • #1
seboastien
53
0

Homework Statement



Find first three non zero terms in series expansion for ln(1+e^-z) when z is very large


Homework Equations






The Attempt at a Solution



I've got as far as ln(1+e^(-1/z)*e^((1/z)(z^(2) - 1))

not sure where to go from here
 
Physics news on Phys.org
  • #2
seboastien said:
Find first three non zero terms in series expansion for ln(1+e^-z) when z is very large

Maybe series (19) on this page http://mathworld.wolfram.com/SeriesExpansion.html" would be a good start. Just check that your conditions satisfy the inequality so the series will be sure to converge.
 
Last edited by a moderator:

FAQ: Power series when variable is very large

What is a power series when the variable is very large?

A power series is a mathematical expression that represents a function as an infinite sum of terms. When the variable in the series is very large, it means that the value of that variable is approaching infinity.

How do you determine the convergence of a power series when the variable is very large?

The convergence of a power series when the variable is very large can be determined by using the Ratio Test or the Root Test. These tests compare the infinite series to a geometric series with a known convergence value.

Can a power series diverge when the variable is very large?

Yes, a power series can diverge when the variable is very large. This occurs when the terms of the series do not approach zero as the variable approaches infinity, making it impossible for the infinite sum to have a finite value.

How can power series be used to approximate functions when the variable is very large?

Power series can be used to approximate functions when the variable is very large by truncating the series to a finite number of terms. This finite sum can then be used as an approximation for the function, with the accuracy increasing as more terms are included.

Are there any real-world applications of power series when the variable is very large?

Yes, power series with large variables have many real-world applications, such as in physics, engineering, and economics. They can be used to model and approximate complex phenomena, such as the behavior of gases at high temperatures or the growth of populations over time.

Similar threads

Replies
12
Views
2K
Replies
13
Views
2K
Replies
2
Views
1K
Replies
1
Views
2K
Replies
2
Views
1K
Replies
3
Views
1K
Back
Top