Hi everyone,
The answer key for the Final Exam Review Sheet is now complete (it can be found in Classroom Resources / Exam Reviews ).
Regards,
Prof. Reitz
Category: Resources
Getting Started, How-Tos, and so on
Hi everyone,
The review sheet for the final exam has been posted under Classroom Resources / Exam Reviews. As always, let me know in person, by email, or here on the OpenLab if you have any questions.
NOTE: The Review Sheet contains solutions to most, but not all, problems – the rest of the solutions will be added this weekend.
Regards,
Prof. Reitz
Hi everyone,
The review sheet for Exam #3, taking place on Tuesday 11/27, is posted under Classroom Resources / Exam Reviews. As always, if you have any questions or notice any errors please let me know (by email, in person, or here on the OpenLab).
Best,
Prof. Reitz
UPDATE: The exam will cover through Sec 2.9 only. Problem #16 on the review sheet will NOT be on the exam (although it may appear on the second exam).
The first exam will take place on Tuesday, October 2nd. The review sheet is posted under “Classroom Resources/Exam Reviews” – it is the same as last year’s Exam #1 Review. Please let me know if you have any questions, or to report an error.
Regards,
Prof. Reitz
Hi everyone,
I’m writing to follow up on a discussion we had in class today, regarding methods for translating conditional (“if…then”) statements from English to symbols.
We started with:
If it rained, the ground got wet.
Which we symbolized as
R -> W
Where R = “it rained” and W = “the ground got wet”.
We then got stuck on the phrase:
It rained only if the ground got wet.
The correct symbolic version of this is:
R -> W
just as it appeared in the slides, where R = “it rained” and W = “the ground got wet”, just as before. This is counterintuitive, but true!
For a longer discussion, with some better examples, take a look at this page (otherwise, just memorize it!):
https://criticalthinkeracademy.com/courses/2514/lectures/51574
WeBWorK is accessible from on and off campus (anywhere you have access to the internet). Your first WeBWorK assignment is due on Tuesday, September 4th, at midnight, and will cover the material from the second day of class. Here’s what you have to do:
Assignment. To get started , you must complete the following three steps.
Step 1. Log in to WeBWorK here: http://mathww.citytech.cuny.edu/webwork2/MAT2071-F18-Reitz. I have created Usernames and Passwords for each student registered for my class.
Username. Your username for WeBWorK consists of your first initial plus your last name, all lowercase (for example, John Smith would have username ‘jsmith’).
Password. Your temporary password is the same as your username (if your username is ‘jsmith’, your password is currently ‘jsmith’).
Step 2. Change your password and update your email address. To do this, select “Password/Email” from the main menu on the left. Use whatever email address you like (I suggest using one that you check often).
Step 3. Complete the first assignment, titled Assignment1-Sec1.2-1.3. Click on an assignment on the main screen to get started.
If you have any trouble – either with logging in, or with completing the assignment, post a comment here or send me an email and I will get back to you.
WeBWorK Tips:
- Click on a problem to see the details (the list of problems appears in the menu on the left). Enter an answer and hit “Submit Answers”. Don’t worry, if you get it wrong you can try it again.
- You can work on the problems in any order you wish. You can do some problems now, and come back and do the rest another day (your work will be saved, as long as you submit your answers).
- If you want to print out a copy of the assignment, click on the assignment name in the main menu on the left, and then click the link in the main screen area that reads “Download a hardcopy of this homework set.”
This course is MAT 2071, Introduction to Proofs and Logic, taking place in the Fall 2018 semester with Professor Reitz. We will be using this website in a variety of ways this semester – as a central location for information about the course (assignments, review sheets, policies, and so on), a place to write about the work we are doing, to ask and answer questions, to post examples of our work, and to talk about logic, proofs, mathematics, reality and so on.
Getting Started
Anyone on the internet can look around the site and see what we are doing, and even leave a comment on one of the pages. However, only registered users can create new posts and participate in the discussion boards.
How do I register?
You will need to do two things:
- If you have not used the OpenLab before, you must first create an account. You will need access to your citytech email address for this. Detailed instructions for signing up on the OpenLab can be found here.
- Once you have created an account on the OpenLab, log in and then join this particular course, 2018 Fall – MAT 2071 Proofs and Logic – Reitz. To do this, first click the “Course Profile” link at the top left of this page (just under the picture). Then click the “Join Now” button, which should appear just underneath the picture there.
Problems with the OpenLab or with your CityTech email:
Please let me know if you run into any problems registering or joining our course (send me an email, jreitz@citytech.cuny.edu). I also wanted to give you two resources to help out in the process:
1. For problems with your citytech email account, contact the Student Computing Helpdesk, either in person, by phone, or by email:
Student Computing Helpdesk
Location: Library Building, First Floor (L-114)
Hours: TBD
Phone: 718.260.4900
E-mail: Studenthelpdesk@citytech.cuny.edu
Their website also contains tutorials and FAQ on common problems
2. For problems registering for the OpenLab, contact the OpenLab support team, either by email at openlab@citytech.cuny.edu, or by following this link.
Logic on Math StackExchange
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- Prove $\forall x \forall y(xEy \rightarrow \neg x=y)$ in the vocabulary of graphs April 22, 2024Problem: Prove the sentence $\forall x \forall y(xEy \rightarrow \neg x=y)$ in the vocabulary of graphs using the axioms of graph theory. So far: The axioms of graph theory given are antireflexivity and symmetry. Here $xEy$ means there's an edge between the vertices $x$ and $y$. We were told we'd need identity axioms for this […]categoricallystupid
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