You are Here: Home >< Maths

# How to find Eigenvectors? Watch

1. I know how to find the eigenvalues (lambda) and then I can put them back into that A - Lambda*I matrix, and then I know you have to multiply this by a general vector 'v'. Lets assume for now that it's a 2 x 2 matrix, so v= (x,y). And I also know that you let all this equal to 0. You then multiply out the matrix and you get 2 equations that equal 0. What do you do from here?
2. Solve those equations and express one component in terms of the other. (There isn't a unique solution. If you have a unique solution then you have made an error.)
3. (Original post by Zhen Lin)
Solve those equations and express one component in terms of the other. (There isn't a unique solution. If you have a unique solution then you have made an error.)
Can you pick 4 random numbers so we can create an example because the bit I have trouble with is that whole expressing one in terms of the other and how to write that down. If you pick 4 numbers then you're not giving me a solution to my homework and mods can't do anything about that right
4. (Original post by claret_n_blue)
Can you pick 4 random numbers so we can create an example because the bit I have trouble with is that whole expressing one in terms of the other and how to write that down. If you pick 4 numbers then you're not giving me a solution to my homework and mods can't do anything about that right
Take a 2x2 matrix:

The eigenvalues are 7 and 2.

Take the eigenvalue 7 and put it into the equation and you get:

The equations are:

-2x + 3y = 0
2x - 3y = 0

These are both 3y = 2x

Let x=k

y= (2/3)k

The eigenvector is therefore

Which can be written as:

A similar thing can be done with the eigenvalue 2.

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:
Updated: December 2, 2010
Today on TSR

### Degrees to get rich!

... and the ones that won't

### Women equal with Men?

Discussions on TSR

• Latest
• ## See more of what you like on The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

• Poll
Useful resources

### 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

## Groups associated with this forum:

View associated groups
Discussions on TSR

• Latest
• ## See more of what you like on The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

• 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.