21260 Differential Equations
Assignments: Week #12
 Reading:
 Monday: Section 7.8, pp 401405.
 Wednesday: Review secondorder, linear, homogeneous equations.
 Friday: Section 9.1.

 Exercises:
Due at the start of class on Wednesday 12 November.
 #7.4.5, 7.5.3, 7.5.11,
7.6.2, 7.6.4.
 #7.4.6, 7.5.8, 7.5.12, 7.6.8.
 #7.5.31, 7.6.13.
 Notes:
 For problems 7.5.3 and 7.6.2, you should sketch some trajectories
by hand. You do not need to draw the direction field. Your sketch
should indicate the straight line solutions, and the qualitative
behavior of some other solutions (behavior at t approaches plus or
minus infinity). For systems with complex eigenvalues, show the
direction of the spiral (clockwise/counterclockwise) and whether
solutions move toward or away from the origin.
 For other problems that ask for a direction field or trajectories
of solutions, you may use the Java Applet pplane if you wish. (See News for
Thursday 6 November.) If you choose to do these problems by hand,
follow the advice above.