Exam 2 Grading
Posted: Mon Nov 02, 2009 3:55 pm
- 10 points each for (a)-(d), pretty much all or nothing. One common mistake was assuming the maximum velocity was at the end of the graph: -4. There was nothing in the problem to indicate that.
- 5 points for parts (a) and (b), 20 points for part (c).
- wrong sign: -1
- common mistakes:
- no summation: -2
- missing part of equation: -2
- exp(3t) not evaluated at t=0: -2
- 5 points for recursion relation
- 5 points for right coefficient evaluations for a0-a5
- 5 points for proper substitution into the differential equation
- 5 points for manipulating the series correctly to isolate powers of t.
- 5 points for correct series form for x(t) and x''(t)
- 5 points for correct substitution
- 10 points for manipulating equation to isolate powers of t (5 for series, 5 for terms because the different series started at different index values)
- 5 points for the recursion relation
- 5 points for correct a0-a5.