# Math 115A announcements

• (Dec 12) Solutions to the final are available here.
• (Dec 10) Final grades are available here.  The average score on the final was 61%, with a standard deviation of 20%.  The easiest question was Q8 (average score 70%), with Q3, Q4, Q6 being close runners up; the hardest questions were Q7 and Q5 (29% each).
• (Nov 25) Some typos in the Week 6 and Week 7 notes have been fixed.  In particular: in Corollary 13 of Week 6, "independent" should read "dependent".  On page 10 of Week 7,"D e_j = lambda_j" should read "D e_j = lambda_j e_j".  Thanks to Doug for pointing these out.
• (Nov 18) The TA's Tuesday office hours this week (Tuesday, Nov 19) have been moved from 2-3pm to 12-1pm.  Next week they will be back to normal.
• (Nov 18) There are some typoes in the Fibonacci example at the end of the week 7 notes: several minus signs are missing, and the strange "frac 1 sqrt(5)" should read "1 / sqrt(5)" instead.  These are now fixed.
• (Nov 1) Midterm grades are available in Microsoft Excel format here. Mean grade was 30 out of 50 (with a standard deviation of 10), and the median grade ws also 30. The hardest questions were questions 2 (mean 4.8, standard deviation 2.4), and questions 5 (mean 4.0, standard deviation 3.0).  Question 5 had the highest correlation (82%) with the midterm grade, which meant that it was the question that best measured your overall ability in the course (it was, after all, the hardest question in the midterm, as it really required one to really understand the concepts of null space and range, and to try to experiment with several possible linear transformations).  For reference, the midterm itself is available here.  Midterm solutions are available here.
• (Oct 30) There is an erratum to Assignment 5: In Question 9, all occurrences of "isomorphic" should read "similar" instead.
• (Oct 29) Some typos to the week 4 and 5 notes fixed.  In particular, the midterm excludes Section 1.7, not Section 1.6 (sorry!)
• (Oct 24) Solutions to the practice midterm are now available.
• (Oct 23) Another typo in the week 3 notes (now fixed) - some of the column vectors on pages 20 and 23 were missing some trailing zeroes.  Thanks to Rory Laster for pointing these out.
• (Oct 21) There were some errors in the week 3 notes on pages 29 and 30, where certain subscripts and superscripts had been switched.  These have now been fixed.  (With the matrix representation of linear transformation, the basis for the range is always on top, and the basis for the domain is on the bottom).
• (Oct 10) The link to the supplemental handout on set theory has been fixed.  (Sorry!)
• (Oct 8) There is an erratum to Assignment 2: In the Hint for Question 7, the "Dimension Theorem" should read "Corollary 1 of the Week 2 notes".
• (Oct 7) Linear algebra deals a lot with sets - vector spaces are sets of vectors, and so are bases, etc.  Since some of you have not had much exposure to set theory, I've prepared a supplemental handout on set theory to go with the class notes.
• (Oct 6) There is an erratum to Assignment 1: In Question 6, "Section 1.2" should read "Section 1.3".  I.e. you should do Exercise 8(aef) of Section 1.3 of the textbook.
• (Oct 5) Since one or two students have been asking about computing requirements (e.g. Maple use) for this course, I'll clarify here that there is no computing component to this course.  (Actually, this course will be mostly theoretical, instead of computational).
• (Oct 2) This class is now closed.  Those who are on the wait list will be added, and those who have received PTEs can enroll, but otherwise there will be no further additions to the class; it is already about 10 students over capacity.  There may still be room in the other sections, though.