Day 22: General CasePosted: September 30, 2013
This was a student trying to make an argument about, I think (it’s been a couple days since then, to be honest), displacement being negative. While the argument doesn’t seem to be correct looking at the picture, I was impressed at the time mostly with how the student generalized the argument by trying to explain it symbolically, rather than resort to specific cases which students usually do. I think he wanted x2 to be less than x1, not greater. Also, there is a partially erased delta next to the x on the bottom.