Can a real matrix have complex eigenvectors?

Can a real matrix have complex eigenvectors?

Since a real matrix can have complex eigenvalues (occurring in complex conjugate pairs), even for a real matrix A, U and T in the above theorem can be complex.

What matrices have complex eigenvalues?

Matrices with Complex Eigenvalues. As a consequence of the fundamental theorem of algebra as applied to the characteristic polynomial, we see that: Every n × n matrix has exactly n complex eigenvalues, counted with multiplicity.

Can Hermitian matrix have complex eigenvectors?

Moreover, a Hermitian matrix has orthogonal eigenvectors for distinct eigenvalues. Even if there are degenerate eigenvalues, it is always possible to find an orthogonal basis of Cn consisting of n eigenvectors of A.

Can complex eigenvalues be repeated?

We say an eigenvalue λ1 of A is repeated if it is a multiple root of the characteristic equation of A—in other words, the characteristic polynomial |A − λI| has (λ − λ1)2 as a factor.

What is complex matrix?

A complex matrix is a matrix that has some complex number among its elements. Remember that a complex or imaginary number is a number made up of a real part and an imaginary part, which is indicated by the letter i.

Can symmetric matrices have complex eigenvalues?

Symmetric matrices can never have complex eigenvalues.

What is complex matrix with example?

A complex matrix is a matrix that has some complex number among its elements. Remember that a complex or imaginary number is a number made up of a real part and an imaginary part, which is indicated by the letter i. For example: The real part of the complex number above is 3, and its imaginary part is 5.

What is a complex eigenvalue?

Geometry of 2 × 2 Matrices with a Complex Eigenvalue. Let A be a 2 × 2 matrix with a complex, non-real eigenvalue λ . Then A also has the eigenvalue λ B = λ . In particular, A has distinct eigenvalues, so it is diagonalizable using the complex numbers.

How to find complex eigenvalues?

complex eigenvalues. Since eigenvalues are roots of characteristic polynomials with real coe¢cients, complex eigenvalues always appear in pairs: If ‚0=a+bi is a complex eigenvalue, so is its conjugate ‚¹ 0=a¡bi: For any complex eigenvalue, we can proceed to &nd its (complex) eigenvectors in the same way as we did for real eigenvalues

How to plot complex eigenvalues of a matrix?

function [e] = plotev(n) % [e] = plotev(n) % % This function creates a random matrix of square % dimension (n). It computes the eigenvalues (e) of % the matrix and plots them in the complex plane. % A = rand(n); % Generate A e = eig(A); % Get the eigenvalues of A close all % Closes all currently open figures.

What is the minimum and maximum number of eigenvectors?

The minimum vertex degree is non-negative, while the least eigenvalue is non-positive, so the equality is attained iff the minimum degree=least eigenvalue=0, which further corresponds to the graph without edges known as the empty (or totally disconnected) graph. Its only eigenvalue is 0, and the maximum vertex degree is also 0.

What are generalized eigenvectors?

The generalized eigenvectors of a matrix are vectors that are used to form a basis together with the eigenvectors of when the latter are not sufficient to form a basis (because the matrix is defective). We start with a formal definition. Definition Let be a matrix. Let be an eigenvalue of .