Matrix Exponential Homework: Eigenvalues & Eigenvectors

BearY
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Homework Statement


Show that if ##λ##and ##V ## are a pair of eigenvalue and eigenvector for matrix A, $$e^Av=e^λv$$

Homework Equations


##e^A=\sum\limits_{n=0}^\infty\frac{1}{n!}A^n##

The Attempt at a Solution


I don't know where to start.
 
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I'd use a lower case ##v## or better ##\mathbf v## here. (I've never seen capitalized vectors?)
BearY said:

Homework Equations


##e^A=\sum\limits_{n=0}^\infty\frac{1}{n!}A^n##
The power series is quite instructive. Each side is some matrix that is a function of ##A##. What happens if you multliply each side by an eigenvector of A? The idea is there are a lot of moving parts here... if you can find a fixed point maybe it isn't so hard.
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btw, do you know why the series is convergent for matrices? This is a bit subtler of a question.
 
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BearY said:

Homework Statement


Show that if ##λ##and ##V ## are a pair of eigenvalue and eigenvector for matrix A, $$e^AV=e^λV$$

Homework Equations


##e^A=\sum\limits_{n=0}^\infty\frac{1}{n!}A^n##

The Attempt at a Solution


I don't know where to start.

Start with ##A V = \lambda V##. What are ##A^2 V##, ##A^3 V##, etc.?
 
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Thread locked as the OP has shown no effort.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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