And another bugfix (a single character) in spring 2017

I see that the version posted a week ago, missed a "/" in 2(b): somewhere therein, a "1/t" was only "1t", and that does make enough difference to update. 

Message from a week ago:

It was pointed out to me a "new" kind of error: in the solution note for spring 2017, not even the questions of problem 3 were right. The reason was that the "final" version was deleted by mistake (my bad, of course) and what you saw was the most recent that was still left. I have reconstructed and re-uploaded; see disclaimer page 1, and note that in addition there is a correction in problem 2 as well.