Complex Eigenvectors: Showing A(ReV) and A(ImV)

Click For Summary
SUMMARY

The discussion centers on proving the relationships A(Re(v)) = aRe(v) + bIm(v) and A(Im(v)) = -bRe(v) + aIm(v) for a 2x2 matrix A with a complex eigenvalue λ = a - bi, where b ≠ 0. The proof begins by expressing the eigenvector v as v = Re(v) + iIm(v) and expanding A(v) = (a - bi)v. The clarity that A is a real matrix is emphasized as essential for the proof's validity.

PREREQUISITES
  • Understanding of complex eigenvalues and eigenvectors in linear algebra.
  • Familiarity with matrix operations and properties of 2x2 matrices.
  • Knowledge of real and imaginary components of complex numbers.
  • Ability to manipulate complex expressions and perform algebraic expansions.
NEXT STEPS
  • Study the properties of complex eigenvalues in 2x2 matrices.
  • Learn about the geometric interpretation of eigenvectors in the complex plane.
  • Explore proofs involving linear transformations and their effects on complex vectors.
  • Investigate the implications of real matrices having complex eigenvalues.
USEFUL FOR

Students studying linear algebra, mathematicians focusing on eigenvalue problems, and educators teaching complex vector spaces will benefit from this discussion.

Shaunzio
Messages
16
Reaction score
0

Homework Statement


Let A be a 2x2 matrix with complex eigenvalue (lambda)=a-bi, (b does not equal 0) and associated eigenvector v-> C^2. Show that A(Rev)=aRev +bImv and A(ImV)=-bRev +aImv. Where Re is real part and I am is imaginary part.


Homework Equations





The Attempt at a Solution


I am terrible at proofs and I am no idea how one would show this..
 
Physics news on Phys.org
They should probably make it clear A is real matrix. Start by using v=Re(v)+i*Im(v) and expand A(v)=(a-ib)v in terms of Re(v) and Im(v). There really aren't any tricks here.
 

Similar threads

  • · Replies 4 ·
Replies
4
Views
1K
  • · Replies 1 ·
Replies
1
Views
5K
  • · Replies 1 ·
Replies
1
Views
2K
Replies
8
Views
2K
  • · Replies 7 ·
Replies
7
Views
1K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 27 ·
Replies
27
Views
2K
  • · Replies 5 ·
Replies
5
Views
14K
Replies
20
Views
2K
  • · Replies 3 ·
Replies
3
Views
1K