Suppose A is a 2 x 2 matrix that has a repeated eigenvalue A with linearly independent eigenvectors and . Note that since A(avi + 352) = Aavi + Αβύ, = αλΰι + βαΰ, = αλύ, + βλΰg = λ(αύ1 + B52) the vector au + Bu₂ is also an eigenvector for A. Since ₁ and 2 are linearly independent we can scale them using a and 8 and add the scaled vectors together to get any nonzero vector 3 in the plane. (Think of ₁ and 2 as arrows in the plane and how you could scale and combine them as in the figure below.) BEZ V3 = avi + βV So in fact every nonzero vector 3 is an eigenvector for A! In particular, the vectors H eigenvectors for the eigenvalue A. This tells us that if A is a 2 x 2 matrix that has a repeated eigenvalue A with linearly independent eigenvectors then A has to have the following form: 91 and H are

Advanced Engineering Mathematics
10th Edition
ISBN:9780470458365
Author:Erwin Kreyszig
Publisher:Erwin Kreyszig
Chapter2: Second-order Linear Odes
Section: Chapter Questions
Problem 1RQ
icon
Related questions
Question
Suppose \( A \) is a \( 2 \times 2 \) matrix that has a repeated eigenvalue \( \lambda \) with linearly independent eigenvectors \( \vec{v}_1 \) and \( \vec{v}_2 \). Note that since

\[
A(\alpha \vec{v}_1 + \beta \vec{v}_2) = A\alpha \vec{v}_1 + A\beta \vec{v}_2 = \alpha A\vec{v}_1 + \beta A\vec{v}_2 = \alpha \lambda \vec{v}_1 + \beta \lambda \vec{v}_2 = \lambda (\alpha \vec{v}_1 + \beta \vec{v}_2)
\]

the vector \( \alpha \vec{v}_1 + \beta \vec{v}_2 \) is also an eigenvector for \( \lambda \). Since \( \vec{v}_1 \) and \( \vec{v}_2 \) are linearly independent, we can scale them using \( \alpha \) and \( \beta \) and add the scaled vectors together to get any nonzero vector \( \vec{v}_3 \) in the plane. (Think of \( \vec{v}_1 \) and \( \vec{v}_2 \) as arrows in the plane and how you could scale and combine them as in the figure below.)

*Diagram Description:*
The diagram illustrates vectors \( \vec{v}_1 \), \( \vec{v}_2 \), and \( \vec{v}_3 = \alpha \vec{v}_1 + \beta \vec{v}_2 \). Vector \( \vec{v}_1 \) is shown as an arrow in one direction, \( \vec{v}_2 \) is shown in another direction, and the combination \( \vec{v}_3 \) is shown as the resultant vector summing both scaled vectors.

So in fact every nonzero vector \( \vec{v}_3 \) is an eigenvector for \( A \)! In particular, the vectors \(\begin{bmatrix} 0 \\ 1 \end{bmatrix}\) and \(\begin{bmatrix} 1 \\ 0 \end{bmatrix}\) are eigenvectors for the eigenvalue \( \lambda \). This tells
Transcribed Image Text:Suppose \( A \) is a \( 2 \times 2 \) matrix that has a repeated eigenvalue \( \lambda \) with linearly independent eigenvectors \( \vec{v}_1 \) and \( \vec{v}_2 \). Note that since \[ A(\alpha \vec{v}_1 + \beta \vec{v}_2) = A\alpha \vec{v}_1 + A\beta \vec{v}_2 = \alpha A\vec{v}_1 + \beta A\vec{v}_2 = \alpha \lambda \vec{v}_1 + \beta \lambda \vec{v}_2 = \lambda (\alpha \vec{v}_1 + \beta \vec{v}_2) \] the vector \( \alpha \vec{v}_1 + \beta \vec{v}_2 \) is also an eigenvector for \( \lambda \). Since \( \vec{v}_1 \) and \( \vec{v}_2 \) are linearly independent, we can scale them using \( \alpha \) and \( \beta \) and add the scaled vectors together to get any nonzero vector \( \vec{v}_3 \) in the plane. (Think of \( \vec{v}_1 \) and \( \vec{v}_2 \) as arrows in the plane and how you could scale and combine them as in the figure below.) *Diagram Description:* The diagram illustrates vectors \( \vec{v}_1 \), \( \vec{v}_2 \), and \( \vec{v}_3 = \alpha \vec{v}_1 + \beta \vec{v}_2 \). Vector \( \vec{v}_1 \) is shown as an arrow in one direction, \( \vec{v}_2 \) is shown in another direction, and the combination \( \vec{v}_3 \) is shown as the resultant vector summing both scaled vectors. So in fact every nonzero vector \( \vec{v}_3 \) is an eigenvector for \( A \)! In particular, the vectors \(\begin{bmatrix} 0 \\ 1 \end{bmatrix}\) and \(\begin{bmatrix} 1 \\ 0 \end{bmatrix}\) are eigenvectors for the eigenvalue \( \lambda \). This tells
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 3 steps with 3 images

Blurred answer
Recommended textbooks for you
Advanced Engineering Mathematics
Advanced Engineering Mathematics
Advanced Math
ISBN:
9780470458365
Author:
Erwin Kreyszig
Publisher:
Wiley, John & Sons, Incorporated
Numerical Methods for Engineers
Numerical Methods for Engineers
Advanced Math
ISBN:
9780073397924
Author:
Steven C. Chapra Dr., Raymond P. Canale
Publisher:
McGraw-Hill Education
Introductory Mathematics for Engineering Applicat…
Introductory Mathematics for Engineering Applicat…
Advanced Math
ISBN:
9781118141809
Author:
Nathan Klingbeil
Publisher:
WILEY
Mathematics For Machine Technology
Mathematics For Machine Technology
Advanced Math
ISBN:
9781337798310
Author:
Peterson, John.
Publisher:
Cengage Learning,
Basic Technical Mathematics
Basic Technical Mathematics
Advanced Math
ISBN:
9780134437705
Author:
Washington
Publisher:
PEARSON
Topology
Topology
Advanced Math
ISBN:
9780134689517
Author:
Munkres, James R.
Publisher:
Pearson,