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Topic: Regular Perturbation series question
Replies: 3   Last Post: Feb 8, 2012 7:16 AM

 Messages: [ Previous | Next ]
 MTBrenneman@gmail.com Posts: 983 Registered: 8/21/06
Regular Perturbation series question
Posted: Feb 6, 2012 3:48 PM

Hi,

I am trying to find the soln to:
(i) (1+x)^3 = e*x where e<<1
using a regular perturbation series.

When I try substituting in the regular perturbation series:
(ii) x = x0 + e*x1 + e^2*e2 +...
I cannot get a solution

If I try to rewrite it as:
(iii) 1 + x = e^(1/3) x^(1/3)
substitute (ii) into (iii) and expand out the RHS using the
generalized binomial formula, I cannot get the powers of e to match
up.

I know there is a soln to this problem, but I can't see what I'm
messing help. Can anyone give me a hint as to what I am doing wrong or
missing?

TIA,
Matt

Date Subject Author
2/6/12 MTBrenneman@gmail.com
2/7/12 RGVickson@shaw.ca
2/8/12 Thomas Nordhaus
2/8/12 Thomas Nordhaus