I'm rather unsure what is going on with the last part of question c any help would be

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Diagonalizable matrix used in polynomial form?

Homework Statement



[PLAIN]http://img163.imageshack.us/img163/4992/photo1mpl.jpg

Homework Equations





The Attempt at a Solution



I'm rather unsure what is going on with the last part of question c any help would be greatly appreciated!

I have the other parts
 
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Can you rewrite B3 and B4?
See a pattern?
 


Hmm.. I'm not really seeing a pattern, so:B^3=8*B^2-9*B-18*identity(3)

and

B^4=9*B^3-19*B^2+9*B-18*identity(3)

not spotting a pattern there
 


LHS said:

Homework Statement



[PLAIN]http://img163.imageshack.us/img163/4992/photo1mpl.jpg

Homework Equations





The Attempt at a Solution



I'm rather unsure what is going on with the last part of question c any help would be greatly appreciated!

I have the other parts

Is this from a take-home test?
 
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no don't worry, I'm going through past exam questions and there's nothing in my notes that can help me with this one..
 


LHS said:
Hmm.. I'm not really seeing a pattern, so:


B^3=8*B^2-9*B-18*identity(3)

and

B^4=9*B^3-19*B^2+9*B-18*identity(3)

not spotting a pattern there

Your equations contain B2.
But you have an equation for B2 that you can substitute.
Can you do so?

Then for B4 your equation contains B3. Can you substitute the result that you just got?
 
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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