MAT244-2013S > Quiz 4

Quiz 4--Problem (night sections)

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Sabrina (Man) Luo:

--- Quote from: Matthew Cristoferi-Paolucci on March 20, 2013, 09:33:06 PM ---Some classifications for part b

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For the Thrid Matrix A: Det(A) should be r^2+r+3=0, and r=-1/2Â±i sqrt 11/2

Victor Ivrii:

--- Quote from: Sabrina (Man) Luo on March 21, 2013, 06:37:10 AM ---
--- Quote from: Matthew Cristoferi-Paolucci on March 20, 2013, 09:33:06 PM ---Some classifications for part b

--- End quote ---
For the Thrid Matrix A: Det(A) should be $r^2+r+3=0$, and $r=-1/2\pm i \sqrt{ 11}/2$

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Which point you are talking about?

Sabrina (Man) Luo:
I am talking about the second picture (classification of part b), the written solution of the third equilibrium part. There is a calculating error. I just corrected it.

Sabrina (Man) Luo:

--- Quote from: Sabrina (Man) Luo on March 21, 2013, 01:23:04 PM ---I am talking about the second picture (classification of part b), the written solution of the third equilibrium part. There is a calculating error. I just corrected it.

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Victor Ivrii:
I converted your attachment in .doc format (which is not a graphics format and I allow to post it "just in case") to png. Still the picture is correct near equilibrium points but not completely correct globally. We already know that $x=-2$ consists of solutions and thus cannot be crossed by other solutions.

--- Quote from: Sabrina (Man) Luo on March 21, 2013, 11:01:47 PM ---
--- Quote from: Sabrina (Man) Luo on March 21, 2013, 01:23:04 PM ---I am talking about the second picture (classification of part b), the written solution of the third equilibrium part. There is a calculating error. I just corrected it.

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We have 4 points $(-2,0)$, $(0,0)$, $(-1,-1)$ and $(2,2)$. Which of them? Why one needs to look at not properly oriented crappy snapshot to learn what point you are referring to?

Still I am waiting for someone to post computer simulation picture. I am also waiting for answer to the bonus problem. I will post by myself during weekend and topic will be closed.