## ranyai12 3 years ago Can Someone Please Help!! I don;t know what I'm doing wrong!! (The question and my work is attached) http://assets.openstudy.com/updates/attachments/501ec235e4b0be43870f0563-ranyai12-1344193091852-math216new.jpg http://assets.openstudy.com/updates/attachments/501ec235e4b0be43870f0563-ranyai12-1344193118071-img_07531.jpg

1. ranyai12

@Spacelimbus

2. Spacelimbus

hmm I can't see the error myself yet, my only guess could be with the fixated values.

3. ranyai12

i know that the 3 is wrong but idk why

4. Spacelimbus

The Jacobian Matrix looks right to me too, have you tried with different fixated values? other critical points I mean, I see you have found three of them.

5. ranyai12

yea and they all seem to be wrong somehow one of the values in the jacobian end up being wrong

6. Spacelimbus

so it seems like the critical points are the problem then, not your setup.

7. Spacelimbus

$\Large x'=y \\ \Large y'=3x-3x^3$ yes?

8. ranyai12

yea

9. ranyai12

but my critical points are correct because in a previous question it asked to solve for all the critical points and this was a follow up question

10. Spacelimbus

yes I see.

11. Spacelimbus

$\Large J(x,y)=\left[\begin{matrix}0 & 1 \\ -9x^2+3 & 0\end{matrix}\right]$

12. ranyai12

I caught my mistake!!!

13. Spacelimbus

oh? Mind to share?

14. Spacelimbus

I haven't seen it yet.

15. ranyai12

when i plugged in the critical poiints into the jacobian there was an algebraic error so the jacobian wouldve been 0 1 -6 0

16. Spacelimbus

point (1,0) huh?

17. ranyai12

yea

18. Spacelimbus

hmm I understand it for that point, but I am not sure why point (0,0) shouldn't work, if it's in fact a critical point.

19. ranyai12

because this question is asking for the first critical point we found, which we had to put in order from lowest value ot highest, and so we had to use (-1,0)

20. Spacelimbus

Oh I understand, I wasn't aware of that. (-: Well, well done!

21. ranyai12

Thank you!!!