Solving equations for Eigenvector: Vanishing

Click For Summary
SUMMARY

The discussion focuses on solving eigenvector equations derived from the matrix ##\begin{bmatrix}9.2196& 6.488\\4.233& 2.9787\end{bmatrix}##. The eigenvalues identified are ##\lambda_1 = 0## and ##\lambda_2 = 12.1983##. The user, Zulfi, struggles with the equations ##9.2196x + 6.488y = 0## and ##4.233x + 2.978y = 0##, which are equivalent and yield solutions that are proportional. The correct approach involves setting one variable, such as ##x = 1##, to find the corresponding value of ##y##, leading to the solution ##\begin{bmatrix}x\\y\end{bmatrix} = \begin{bmatrix}2.7\\1\end{bmatrix}##.

PREREQUISITES
  • Understanding of eigenvalues and eigenvectors
  • Familiarity with matrix multiplication
  • Knowledge of linear algebra concepts
  • Ability to manipulate and solve linear equations
NEXT STEPS
  • Study the process of finding eigenvalues and eigenvectors in linear algebra
  • Learn about normalization techniques for eigenvectors
  • Explore the implications of equivalent linear equations
  • Investigate the geometric interpretation of eigenvectors in vector spaces
USEFUL FOR

Students and professionals in mathematics, particularly those studying linear algebra, as well as anyone working with eigenvalues and eigenvectors in applied fields such as physics and engineering.

zak100
Messages
462
Reaction score
11

Homework Statement


I am trying to solve a Eigen vector matrix:

##\begin{bmatrix}9.2196& 6.488\\4.233& 2.9787\end{bmatrix}\cdot\begin{bmatrix}x\\y\end{bmatrix}-\lambda\begin{bmatrix}x\\y \end{bmatrix}=0##

I have found ##\lambda_1 = 0## and ##\lambda_2 = 12.1983##
However, I can't solve the following equations:
##9.2196x + 6.488y =0 -------(eq.1)##
and ##4.233x + 2.978y =0 ----(eq.2)##

I am multiplying ##(eq.1) ## by ##4.233x## and ##(eq.2)## by ##9.2196##

Some body please guide me how to solve these equations for ##x## and ##y## values.

Zulfi.

Homework Equations


##9.2196x + 6.488y =0 -------(eq.1)##
and ##4.233x + 2.978y =0 ----(eq.2)##​

The Attempt at a Solution


I am multiplying ##(eq.1)## by ##4.233## and ##(eq.2)## by ##9.2196## but both the equations are vanishing. Some body please guide me.

Zulfi.
 
Physics news on Phys.org
zak100 said:

Homework Statement


I am trying to solve a Eigen vector matrix:

##\begin{bmatrix}9.2196& 6.488\\4.233& 2.9787\end{bmatrix}\cdot\begin{bmatrix}x\\y\end{bmatrix}-\lambda\begin{bmatrix}x\\y \end{bmatrix}=0##

I have found ##\lambda_1 = 0## and ##\lambda_2 = 12.1983##
However, I can't solve the following equations:
##9.2196x + 6.488y =0 -------(eq.1)##
and ##4.233x + 2.978y =0 ----(eq.2)##

I am multiplying ##(eq.1) ## by ##4.233x## and ##(eq.2)## by ##9.2196##

Some body please guide me how to solve these equations for ##x## and ##y## values.

Zulfi.

Homework Equations


##9.2196x + 6.488y =0 -------(eq.1)##
and ##4.233x + 2.978y =0 ----(eq.2)##​

The Attempt at a Solution


I am multiplying ##(eq.1)## by ##4.233## and ##(eq.2)## by ##9.2196## but both the equations are vanishing. Some body please guide me.

Zulfi.

The two equations are equivalent. So, you just take the solution of either one.
 
And, it only determines the solution up to a constant multiplier, so you can for example arbitrarily set ##x=1## and then find ##y##.
 
Hi,
Thanks for your response. Answer is different in the slide. I have attached the slide. Please guide me.

Solving Decimal eq for Eigen vectors LDA vanishing_PicOfSlide.jpg
 

Attachments

  • Solving Decimal eq for Eigen vectors LDA vanishing_PicOfSlide.jpg
    Solving Decimal eq for Eigen vectors LDA vanishing_PicOfSlide.jpg
    37.7 KB · Views: 520
In the solution for ##w_1##, the ratio of the components ##\frac{0.8178}{0.5755}## is the same as the ratio ##\frac{9.2196}{6.488}## in your system of equations. So it's the same answer but with different normalization, one where ##x^2 + y^2 = 1##.
 
Hi,
##lambda_2 =12.1983##
I am not able to get the correct answer.

##9.2196x + 6.488y = 12.1983x ##
##9.216x - 12.1983x = -6.488y ##

##\begin{bmatrix}x\\y\end {bmatrix} = \begin{bmatrix}2.7\\1\end{bmatrix}##

Somebody please guide me how can i get the correct answer?
Zulfi.
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
2K
Replies
3
Views
2K
  • · Replies 12 ·
Replies
12
Views
3K
  • · Replies 11 ·
Replies
11
Views
2K
  • · Replies 10 ·
Replies
10
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
14
Views
2K
  • · Replies 1 ·
Replies
1
Views
4K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
2
Views
2K