Proving the Infinite Series: (xlna)^(n-1)/n!

In summary, for an infinite series with the form of [(xlna)^(n-1)]/n!, where n takes on integers from 0 onwards, x is any real number, and a is any positive real number, the Maclaurin series expansion can be used to prove that the series converges to a^x. However, there may be other proofs besides using the Maclaurin series.
  • #1
Kevin Huang
2
0

Homework Statement


Given an infinite series that follows the form [(xlna)^(n-1)]/n!
n takes on integers from 0 onwards
x all real numbers
a all positive real numbers


Homework Equations


Maclaurin series expansion


The Attempt at a Solution


In which for the e^x series expansion plug in xlna into the x from e^x to obtain a^x which is the answer to the infinite summation. However, are there any other proofs besides using Maclaurin? Thanks.
 
Physics news on Phys.org
  • #2
Note that

[tex]e^{ax} = \sum_{n=0}^{\infty} \frac {(ax)^n}{n!}[/tex]

In other words the nth term of this series is [itex](ax)^n/n![/itex]. You have a different series. The nth term of your series is [itex](ax)^{(n-1)}/n![/itex].
 

Related to Proving the Infinite Series: (xlna)^(n-1)/n!

1. What is an infinite series?

An infinite series is a sum of infinitely many terms, typically represented in the form of a sequence. It is called "infinite" because there is no specific number of terms in the series.

2. How do you prove that an infinite series converges?

To prove that an infinite series converges, you can use various methods such as the comparison test, the ratio test, or the integral test. These methods involve comparing the given series to a known convergent or divergent series and determining the convergence or divergence of the given series based on the comparison.

3. What does it mean for an infinite series to diverge?

An infinite series diverges when the sum of its terms approaches infinity, meaning that the series does not have a finite limit. This can happen when the terms of the series do not approach zero or when they alternate in sign indefinitely.

4. Can an infinite series converge to a negative number?

Yes, an infinite series can converge to a negative number. For example, the alternating harmonic series (-1 + 1/2 - 1/3 + 1/4 - 1/5 + ...) converges to ln(2), which is a negative number.

5. What is the relationship between the convergence of an infinite series and the convergence of its terms?

The convergence of an infinite series is dependent on the convergence of its terms. If the terms of a series do not approach zero, the series will diverge. On the other hand, if the terms of a series approach zero, the series may still diverge or converge, and further tests are needed to determine its convergence.

Similar threads

  • Calculus and Beyond Homework Help
Replies
1
Views
321
  • Calculus and Beyond Homework Help
Replies
2
Views
735
  • Calculus and Beyond Homework Help
Replies
3
Views
352
  • Calculus and Beyond Homework Help
Replies
6
Views
1K
  • General Math
Replies
7
Views
1K
  • Calculus and Beyond Homework Help
Replies
8
Views
1K
  • Calculus and Beyond Homework Help
Replies
4
Views
1K
  • Calculus and Beyond Homework Help
Replies
22
Views
3K
  • Calculus and Beyond Homework Help
Replies
4
Views
380
Replies
17
Views
651
Back
Top