 
Summary: Mathematics 3C Summer 3B 2009
Worksheet 6.5, August 27th, TA Grace Kennedy
NAME:
PREP for 9/1: Read text Sections 3.13.3, finish worksheet, start new ones
MY WEBSITE: http://math.ucsb.edu/kgracekennedy/SB093C.html
The material coming up in the next week will be significantly more difficult.
Please try to stay on top of your work and be very conscientious with homework
and worksheets.
1. Consider the following system of differential equations:
dx
dt
= 4  2x  y
dy
dt
= 4  x  2y.
(a) Calculate the vertical and horizontal nullclines.
(b) What are the equilibrium solutions?
(c) Draw a sketch of the fluid flow.
(d) Are the equilibrium solutions stable or unstable?
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