MATH 1090 3.00 MW:
Course Information


Greetings and welcome! (How do I do a smiley in HTML?? (This is a rhetorical question; don't reply.))

I will put announcements here on a continual basis, in reverse chronological order, numbered and dated. Always read this file from bottom to top, by announcement number. Later announcements often assume you have read earlier ones.

Also refresh your browser window whenever you look at this file; you don't want to miss recent announcements by seeing only a cached copy of this file. Clearing disk cache fairly often might be wise, too.

The word "you'' appearing on this page usually refers to an unspecified student enrolled in MATH 1090 M and reading the word. "I'' (in most announcements appearing here, and starting with the two instances near the top of this page) refers to Ganong, course coordinator for MATH 1090 in Winter 2012/2013.

Always check LOWER-numbered announcements here first to catch up with recent postings. Check this course page regularly.

Tutorial: Tuesdays, 6-6:50 p.m., in Curtis J, starting 15 Jan.!

37. (10:44 p.m., Friday, 3 May 2013) Just a few minutes ago I posted grades in this course. I will eventually post here a file with the last five digits of people's student numbers, showing: exam grade and grade on assignment 5. Everyone got 32 out of 32 on Assignment 3 (except people who did not hand in any of assignments 1, 2, 4, 5). If you want to pick up the Assignment 5 paper from me, that can be arranged. Everyone is welcome to look at final exams in my office, with a copy of the marking scheme. I have more urgent stuff to do now than post the above here. I will be submitting grades late for another course (at least three days late...); the last time I was late with grades was in 1999. I have been somewhat let down by the graders in that course, and must now continue to mark the exam in it, given 21 April. Here is the rather generous fiddle I applied to the raw scores on Test 2: Let x be the raw score out of 50 on the back of your test 2 paper. Then the mark y out of 50 which I recorded for you is as follows: If x is less than 17, then y is 2 + (23/15)*(x - 2). Remember that 2 marks were just for spelling one's own name correctly or so. One person in fact had an x of 2. If x is above 17, then y is 25 + (18/23)*(x - 17). Thus, a 2 stays a 2, a 17 becomes a 25, the class average of 24.4 or so out of 50 was fiddled to something like 30.6 out of 50, and a 40 out of 50 was fiddled to a 43. I did not fiddle the exam grades. Many of them were really bad. There were 127 marks available at the exam, and during grading I tossed in a few more marks, making the maximum possible score on the exam around 135. The highest score gotten was 99.9. Several people got 89 or above, and several got 80-89. The fact that so many marks were there for the taking is a built-in fiddle. That people did not take the marks is lamentable. The exam was fairly easy. It was easier than the exam in MATH 1090 the last time I gave it, and easier than a few other 1090 exams I have given.

36. (6:47 p.m., Monday, 15 April 2013) Here are some solutions to our exam, and results so far in the grading. The results are quite bad generally.

35. (1:49 p.m., Wednesday, 10 April 2013) This file together with earlier postings provides solutions to all problems of Assignment 5 except problem 2. I am not sure whether I will take the time to post a solution for problem 2. In fact, let's say I will not. It's getting too close to exam time. Let's say this is the last pre-exam posting.

34. (10:56 p.m., Tuesday, 9 April 2013) Here's a bulletin with content as described in announcement 33. I will not post more here tonight. Not sure about tomorrow.

33. (9:39 p.m., Tuesday, 9 April 2013) I am very short of time, but will try now to say a little about exam preparation. I slept almost all day today because of a persistent headache; felt generally unable to do things; I mention this only to explain why I have not posted more earlier today. Am feeling stronger, better now. I am thinking now that more marks than 100 will be available on the exam. In past offerings of this and other courses I have sometimes made the exam "worth" as much as 120 or 130 marks but recorded the totals people get as "out of 100". One year someone got an exam mark of 116 out of 100 or something. Some of you have asked for solutions of problems on Assgt. 5. I'll type out indications of at least one or two solutions tonight and post them here. Some of you are asking about exercises I proposed at the end of Section 6.5 in the book as well; maybe I will post some such too. VERY short of time; sorry. Something will appear here within 60-90 minutes.

32. (3:33 p.m., Sunday, 7 April 2013) Here is a file concerned with our second class test. The test is graded and will be returned to people who submit Assignment 5 at my office tomorrow (or even just ones who show up to get the test). Some "statistics" for the test are given at the bottom of the file.

31. (7:37 p.m., Saturday, 6 April 2013) Here is what I have called "Bulletin 2". You may find it quite useful for exam preparation. (I already said, also, to use the two earlier test preparation files for exam preparation.)

30. (3:20 p.m., Wednesday, 3 April 2013) Here is what I have called "Bulletin 1". I'll probably post more of these here this week.

29. (12:28 a.m., Wednesday, 3 April 2013) OK, the files for Assignment 5 below are ready.

28. (6:52 p.m., Tuesday, 2 April 2013) LINKS BELOW NOT QUITE READY YET!! SOON... AFTER CLASS TONIGHT. WAIT FOR FINAL VERSIONS. Linked below are two files holding Assignment 5, due on 8 April, by midnight, in Ganong's office. Ganong will be there till around 10 p.m. After that you will have to slide the paper under the door where it will be all bent and crushed and jumbled up with similar papers from other people, etc. Here's the first part of Assignment 5, a .pdf file. Here's the second part of Assignment 5, an HTML file.

27. (11:26 a.m., Wednesday, 27March 2013) First, I am well aware that I was not as well prepared for class last night as I should have been. I think I pretty well avoided actual errors, but an instructor should be so well prepared that proofs just go zippety-zap, no "uh, umm", no hesitation, etc. I do regret that your instructor is not better than he is. He was better ten years ago, even five years ago. The fact that he is now not as good as an instructor SHOULD be is one big reason he is retiring in July after 31 years at York. (There are old farts in the Maths/Stats Department who have been at York 41, 42, 43 years (I know three such people).) Next: About problem 2 on the test, with the 1 bonus mark: My error. I cam up with a certain proof which I liked, but ... Here is what happened: I had had 7 hours' sleep total, for Sunday and Monday night. Especially at my extreme advanced age, that is NOT good. I was originally going to ask people to prove the theorem I put on our test last night, but then decided, No, that's too easy, let's instead ask them to prove THIS theorem: ( A --> (B \/ C) ) --> ( (B --> C) --> (A --> C) ). And I thought I would help people prove this by offering a bonus mark for this kind of proof: (1) A --> (B \/ C) < hyp > (2) B --> C < ass > (3) A < hyp > (4) B \/ C (5) B --> C == (B \/ C == C) < ax. 11 > (6) B \/ C == C (7) C D.T. three times. Of course, line (4) comes from M.P. on certain earlier lines, and lines 6 and 7 come from Eqn on certain earlier lines. I also wanted -- this is another reason I offered the bonus mark -- to encourage people all to give the same kind of proof, so that the grader's job would be easier. But then I ruined this nice problem by forgetting to change the wff I was asking people to prove!.... So my instructions really made no sense. Lots of people noticed that it is far better just to make TWO assumptions and use 2.4.24. So ... in a way, I needlessly caused people to spend time on this problem hoping for a bonus mark (but why not do other problems? -- 1 mark is only 2% of the test mark). But also by forgetting to put the "harder" theorem as problem 2 I made people's lives easier, who just used 2.4.24 with two assumptions. Anyway.. bad instructor, as I said.

I do intend to post a fifth assignment here.

You can turn it in Tuesday night; you can also have until later to hand it in. The last day to submit term work for a Winter term course is 8 April. That is also the last day of classes. But the last MATH 1090 class is on 2 April. I will announce later what days I will be in S625 Ross to accept assignment papers after our last class. I think it is also 90% probable that Test 2 will not be graded completely by our last class. So people would have to get it back from me in my office on, say (this is a guess) 4 or 5 or 8 April, or even later (if they want). More on this later.

26. (4:04 p.m., Sunday, 24 March 2013) I just added some lines at the end of the test preparation file linked below. Also, people with last names which start with the letters V through Z must write the test in Curtis J. Everyone else must write in our usual room, Curtis K.

25. (12:58 a.m., Saturday, 23 March 2013) Here's a file about Assignment 4. I've put complete solutions and the start to a marking scheme. I will return to this file later today.

24. (1:23 a.m., Thursday, 21 March 2013) Here's all of the test preparation file for our upcoming test.

23. (10:27 p.m., Thursday, 14 March 2013) Here's the file explaining how to compute your fiddled score on Test 1. See also announcement 22 below. I encourage people to complain about test marks. If you think too many marks were deducted for things like writing <==> as <--> or omitting angle brackets, talk about it with me. Also talk with me outside class about whether to stay in the course, if you like. Tomorrow is the deadline for dropping without receiving a grade. No one can predict the future, but I will say here that people who got raw (= unfiddled) Test 1 scores below 10 out of 50 are at least 90% likely to fail the course. As I said in the course outline nine weeks ago, the time to bear down in a mathematics course is at the beginning, not at exam time. Very few people in my courses, as I warned in the course outline, do better on the exam than on the class tests.

22. (8:17 p.m., Wednesday, 13 March 2013) First: Everyone still enrolled in the course got a perfect score on Assignment 3. It was due on 5 March, and the only condition for a perfect score was that one not hand it in. No one handed it in. I will assign it the right amount of marks to make it worth 1/5 of the total assignment marks in this course. I intend to give a real Assignment 5. And here is Assignment 4. I hope to post a file later tonight, or tomorrow, with Test 1 fiddles in it.

21. (10:20 p.m., Tuesday, 12 March 2013) Look at the long announcement 20 below also. I promise to post here Assignment 3, due at 7 p.m. at the next class. I will post it here no later than midnight Wednesday, i.e., about 26 hours from now.

20. (4 p.m., Tuesday, 12 March 2013) I announced last week in class that Test 2 will be on 26 March. It will take place in our usual room and, if we need more space, Curtis J, the usual tutorial room. I will announce here later who writes in which room. I also announced last week in class, and handed out printouts of it, that a file had been posted with axiom schemes, theorem schemes and metatheorems for Predicate Logic.

I also gave this link for it.

Here is a file of solutions for, some marking scheme for, and comments on, Test 1. At the bottom of that file are some statistics on marks on Test 1. I will fiddle the marks upward. I basically always fiddle the marks on all my tests in all courses upward after grading them, giving "raw" marks and handing the tests back. People who got VERY LOW SCORES on Test 1 (below 10 out of 50) are STRONGLY advised to drop the course before the drop date, which I think is this Friday. Your marks will not be fiddled upward much at all. Scores like that indicate that you very probably don't know what is going on, and should drop. I will post something here Wednesday or Thursday indicating precisely how the grades will be fiddled upward. I predict that roughly grades around 40 will go up a mark or two, and grades between 15 and 35 will go up 2-4 marks roughly. I use a "piecewise linear" fiddle always -- people in different parts of the grade spectrum get fiddled upward differently. Check here later.

19. (3:56 p.m., Monday, 25 February 2013) It turns out that I have only one small thing to put here today -- a correction about the location of the room Curtis 110. As you know from announcement 17 below, if your last name (surname) begins with a letter from A through K, you are to write the test in Curtis 110. So, actually, if your last name does not fall in that range, you can stop reading right here. I have nothing else test-related to say today, and I hope to see you Tuesday night. [... many lines here about Curtis 110 deleted, later]

18. (9:15 p.m., Sunday, 24 February 2013)

Here is a file about Assignment 2 -- solutions, an indication of a marking scheme. I will be around York for long hours on Monday. If you want to get your assignment paper back Monday you could drop by my office Monday. I'll be around some of Tuesday too. The best time to drop by Monday is between 11 a.m. and 2 p.m. (but I might be out fetching a coffee if you just drop by). I do still want to post something more here related to Test 2, though, maybe, and I am running late with it. It might be as late as 4 p.m. tomorrow. Sorry to keep changing the deadline on you. Maybe check one last time here around 4 p.m. Monday. I'll try to be earlier than that but might not be. I much prefer classes which meet three times a week to ones which meet once....

17. (10:25 a.m., Saturday, 23 February 2013)

Where you go for Tuesday's test:

People whose last names start with letters from A through K (first 11 letters of the alphabet) write the test in Curtis 110. (Curtis 110 is at about the same height off the ground as Curtis K is. To reach it from the main part of Curtis at that height, go west, along the north corridor next to the bank of north-facing windows, almost to the end of the Curtis building, near the Steacie end of the Curtis complex.) People whose last names start with letters from L through Z (last 15 letters of the alphabet) write the test in Curtis K (our usual room). See also the test preparation file posted three days ago. I will probably also post more on the course page on Saturday or Sunday, but I might not. I will not post anything here which is test-related later than 10 p.m. Sunday (so you need not check here after that).

16. (6:50 p.m., 20 February 2013)

Here is the beginning of, indeed most of, a test preparation file for Tuesday. I will post more here this week, so check back.

15. (1:21 a.m., 20 February 2013) I will try to have a test preparation file posted here by 10 p.m. tonight. Our test, as you know, is at 7 p.m. on Tuesday, 26 February. I will also post here which room each student is to go to for the test. Most of you will go to the usual room, but some will go to Curtis 110. We meet in the usual room after the test for two classes' worth of logic (having three normal classes' worth of logic every week, all in one night, thanks to the idiotic York practice of having classes like this).

14. (2:55 p.m., 7 February 2013) I have added the third and final problem to Assignment 2, linked in announcement 13.

13. (9:35 p.m., 6 February 2013)

Here is the beginning of Assignment 2. As I typed elsewhere, expect the third and last problem of this assignment by tomorrow at 3 p.m., here.

12. (8:06 p.m., 6 February 2013) Ouch. I suddenly realized that I had not posted the problems this morning which I said I would post. Assignment 2 is still due at 7 p.m. on 12 Feb., but I will make it shorter than I intended to, and I will give everyone some free marks on it to compensate for causing you to come here to look for a file and not find it. I will post the first two problems here within 90 minutes. I apologize..

11. (8:36 p.m., 30 January 2013) No assignment is due at the next class. I don't have anything to post here now either.

10. (9:54 p.m., 28 January 2013) I added a bunch of stuff to the file linked in the next announcement, tonight. You will easily see, about 1/5 of the way down the file, where the new stuff starts.

9. (10:17 p.m., 23 January 2013) See recent announcements below if you have not already. There is no assignment due sic days from now. But I do intend to suggest some practice exercises from GT, and add comments to them. Check back here for those perhaps tomorrow (though I may post some of them tonight. I will list them in a file linked below: Remarks on the exercises on pages 48-50

8. (5:30 p.m., 23 January 2013)

Here is a file of solutions to, comments on, and a marking scheme for, Assignment 1..

7. (6:35 p.m., 22 January 2013)

Here is a file you will be seeing a lot of in this course, the "Axiom Schemes" and "Theorem Schemes" of Boolean Logic.. You should either have a printout of this file or have access to it online, at every class from now on. We will refer to it often.

6. (7:59 p.m., 16 January 2013)

I do not post stuff here for you to ignore it!
READ all of the course outline. It is a contract
between Ganong and the students in this section of 1090.

People who violate the terms of the contract will regret doing so if they want nice grades. When they come to me saying "we didn't know this or that!", I will often smile and say "It was in the course outline in the first week of class."

Here is the file I promised earlier today, related to Assignment 1, and defining various semantic notation and terminology. The aim is to save time in the next class; I'll assume everyone has read this file.

5. (2:55 p.m., 16 January 2013)

Below is a link to our first assignment, as promised. You may want to wait to look at another file meant as preparation for Assignment 1, before actually doing Assignment 1 in final form. That file is not quite ready yet. I hope it will be ready by ... 9 p.m. today, say. Here is Assignment 1..

4. (2:37 a.m., 12 January 2013)

Here is the course outline for MATH 1090 Section M.

3. (2:37 a.m., 12 January 2013)

Have a look at this file about Club Infinity, and the Undergraduate Listserv.

2. (2:37 a.m., 12 January 2013)

Have a look at this file about study groups and submitting group work for assignments in this course.

Please consider making a group submission with other people in the class (maximum group size is 4 people -- groups can have 1, or 2, or 3, or 4 members). This economizes on grader time and means the grader can do a better and faster job of grading, and more grading, than he could if people insisted always on submitting assignments on their own. (But maybe you strongly prefer a group of size 1, i.e., {you}. That's fine too, of course.)

1. (2:37 a.m., 12 January 2013)

Have a look at this file on academic honesty. It is important that you do.

0. (2:37 a.m., 12 January 2013)

Here is a math joke.

Do not be misled by the above into thinking that I am a nice person. I am not, really. But I like good jokes.