You are Here: Home >< Maths

Radius of convergence and Frobenius method

1. I am solving a differential equation using the Frobenius method, however halfway through, I have introduced a new power series. I have been told that I need to show the radius of convergence of this series. Why would I have to do that?
2. (Original post by claret_n_blue)
I am solving a differential equation using the Frobenius method, however halfway through, I have introduced a new power series. I have been told that I need to show the radius of convergence of this series. Why would I have to do that?
So that you know when it converges For instance, if you introduced a power series whose radius of convergence is zero, your solution isn't going to be of much use.

Without knowing more details I can't give you much more of a helpful answer than this!
3. (Original post by nuodai)
So that you know when it converges For instance, if you introduced a power series whose radius of convergence is zero, your solution isn't going to be of much use.

Without knowing more details I can't give you much more of a helpful answer than this!
It's that same differential equation I've been working on for the past, what, 2 weeks? 3 weeks?

I still can't seem to solve it.

This was just because I got told that I needed to make a point about the radius of convergence.

Seeing as your online, please could you help me wit it.I am really stuck on one bit about solving DE's using Frobenius. I have a recurrance relation as:

Where h , A < 0 and a and E are constants. How do I solve this from here? I can solve DE's using power series if there are two "unkowns" but how do I do it using three?

Write a reply… Reply
Submit reply

Register

Thanks for posting! You just need to create an account in order to submit the post
1. this can't be left blank
that username has been taken, please choose another Forgotten your password?
2. this can't be left blank
this email is already registered. Forgotten your password?
3. this can't be left blank

6 characters or longer with both numbers and letters is safer

4. this can't be left empty
your full birthday is required
1. Oops, you need to agree to our Ts&Cs to register
2. Slide to join now Processing…

Updated: May 3, 2012
TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Today on TSR

Haven't started revising yet?

It's not too late!

Poll
Useful resources

Make your revision easier

Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

How to use LaTex

Writing equations the easy way

Study habits of A* students

Top tips from students who have already aced their exams

Create your own Study Planner

Never miss a deadline again

Thinking about a maths degree?

Chat with other maths applicants

Can you help? Study help unanswered threads

Groups associated with this forum:

View associated groups
Study resources

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.