Bill Goodwine's Courses

Problem 1:

• 10 points for assuming exp(\lambda t) for the homogeneous solution
• 2 points for finding right lambda
• 5 points for right assumption for undetermined coefficients
• 3 points for correct substitution of it
• 2 points for right answer for the undetermined coefficients
• 3 points for the graphs

Problem 2:

• 5 for homogeneous solution
• 10 for assuming right particular solution
• 5 for computing constants correctly
• 5 for correct overall answer

Problem 3: 10 points for choosing a correct method, 10 points for the correct procedure (-1 for each small mistake) and 5 points for the correct answer.

Problem 4:

• 5 points for each part.
• Wrong signs: -1, missing mass: -2, integrating factor in solution: -1, for terminal velocity only using v=0: -1.

Problem 5:

• This was pretty much all or nothing. If the student used the definition of linear: f(a x + b y) = a f(x) + b f(y) in the problem, then the most they missed was a couple points for typos. Without this, the problem was essentially wrong, and they got between 0 and 5 points depending on a few minor things.