How to find eigenvalues and eigenvectors for 5x5 matrix

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Homework Help Overview

The discussion revolves around finding eigenvalues and eigenvectors for a 5x5 matrix, focusing on the challenges associated with using the characteristic equation and the potential for tedious calculations.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss various methods for finding eigenvalues, including the characteristic equation, numerical approximations, and transformations. Some express concern over the tedious nature of the calculations involved, while others suggest alternative approaches or tools.

Discussion Status

There is an ongoing exploration of methods, with some participants suggesting that the problem may be set up for simpler solutions. Others emphasize the difficulty of manual calculations and the potential for errors, while a few offer to assist by providing results if the matrix is shared.

Contextual Notes

One participant notes the requirement to solve the problem by hand, excluding the use of software, which influences the discussion on feasible methods.

DavidLiew
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I got a 5x5 matrix, if use characteristic equation to find the eigenvalues and eigenvectors are very tedious and trouble, so got any method which are easy to calculate?
 
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unless you've got a nice matrix (read diagonal) you're going to have to use some tricks, if you're lucky you can use the tschirnhaus transformation but most likely you'll have to resort to numerical approximations for the eigenvalues (Newtons method or something) then you'll have to churn through to find the nullspace manually

it's pretty tedious work and chances are that you'd end up making an error doing it anyway..
you could just use mathematica or matlab, that'd be easier

if you don't have any of those, post your matrix and I'll give you the results, if you want?
 
I need to do it in paper, can not use software to solve.
 
in that case I'd say you're going to be stuck with inspection, Newtons method or something like it or if you're lucky you may be able to reduce it to an easier polynomial via some transformation

sorry bro
 
If you are given exercises in which you are asked to find eigenvalues of 5 by 5 matrices by hand, I suspect it will have been set up so the characteristic equations have small integer roots. Once you have the polynomials, you might try the "rational root" theorem to narrow your choices.
 
genericusrnme said:
unless you've got a nice matrix (read diagonal) you're going to have to use some tricks, if you're lucky you can use the tschirnhaus transformation but most likely you'll have to resort to numerical approximations for the eigenvalues (Newtons method or something) then you'll have to churn through to find the nullspace manually

it's pretty tedious work and chances are that you'd end up making an error doing it anyway..
you could just use mathematica or matlab, that'd be easier

if you don't have any of those, post your matrix and I'll give you the results, if you want?

Instead of MATLAB or mathematica, he/she might prefer to use Maple.

RGV
 

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