Homework:

The only way to learn mathematics is to do mathematics! The homework problems are an integral part of the course; they are the best and most reliable way to check your progress. Problems will range from fairly standard computations to routine applications of the definitions and formulae, to more difficult problems which will require more thought. You'll have a problem set every week, due on Gradescope at 9.00 am on Wednesdays. Please work out problems neatly - don't hand in your scratch work. Homework will be graded for clarity of exposition as well as correctness. One course goal is to sharpen your mathematical writing skills, and homework is a place to practice. Every week one or two problems will be marked for you to focus on your mathematical exposition. If you'd like to, you could type up these problems using LATEX, a typesetting system that is standard for scientific documents; however, you don't need to. On these problems, you will receive feedback accordingly. Weekly homework will be posted on this page. Some of the homework problems may be used for the exams, thus generally solutions will not be posted, but you may come to office hours to discuss your answers.

We encourage you to form study groups and work together. A good strategy is to try each problem yourself first, then get together with others to discuss your solutions and questions, and finally write up the solutions yourself.

The due date is always Wednesday morning at 9AM, and no late homework will be accepted under any circumstances. (This is as much a courtesy to the grader as an incentive to stay current with the course and not fall behind.) To accommodate situations such as a serious illness or anything else that may arise, your homework score will be multiplied by 1.11 (not to exceed 100%) at the end of the quarter.

It is always recommended that students submit partially-completed assignments even if they are not able to finish the full assignment by the deadline.

Responsibility for understanding

You are expected to understand your submitted work in homework and exams and to be able to verbally explain to your instructor (upon request, and without advance notice) any work you submit. When you apply for jobs, you will be interviewed by professionals who instantly recognize a lack of real understanding due to over-reliance on AI; we hold you to the same standard. Do not submit what you do not understand. The response ``I don't understand what I was writing but I know it works'' is never acceptable when asked to explain a submission. If your verbal explanation is inadequate in that you clearly do not understand what you wrote down or you cannot solve a similar problem using the same techniques, your grade for that portion of the assignment or exam will be assigned (or reassigned) to be 0. Your instructor may also file an Honor Code concern if your work contains solutions resembling AI output that you cannot adequately explain in-person in your own words when asked to do so.

Logistics for handing in homework

The homework is due on Wednesdays at 9.00 am Pacific Time.
Homework submissions will be handled electronically via the Gradescope platform, that is now linked through canvas.

Gradescope accepts only electronic submissions, so you will need to scan your homework before uploading it. Details on how to use Gradescope can be found below.

Assignments will be posted one week before they are due. Any change (e.g., to fix a typo) to a posted assignment will be announced in class and via email.

Untagged problem policy: Untagged homework problems will not be graded by the graders. Once you submit a regrade request due to a problem tagged incorrectly, there will be between 10% and 50% penalty for that problem. (penalty progressing from Hw2).
Due October 1st Homework 1
Due October 8th Homework 2
Due October 15th Homework 3
Due October 22nd Homework 4 TeX source of Bolzano-Weierstrass
Due October 29th Homework 5
Due November 5th Homework 6 TeX source: problem 6
Due November 12th Homework 7
TeX source needed for homework
Due November 19th Homework 8
Due December 3rd Homework 9

Gradescope overview

Gradescope is an online platform for grading exams and homework. For each problem, you will be able to see clearly which rubric items your solution satisfied and any additional comments the grader has for you.

Two important notes:

  • Homework assignments will still be graded by members of the Math 21 instructional team. You are not being graded by an electronic system.
  • Students are still responsible for scanning and uploading their homework each week.

How do I actually upload my homework?

For each homework assignment, you must

  • Produce a legible PDF of your complete solutions to each problem. Make sure your problems are clearly labeled!
  • Upload the PDF to Gradescope by the deadline (9AM on Wednesday mornings)
  • Select the page(s) that contain the solution to each of the assigned problems. Note: Failure to do this finalizing step will mean that some or all of your problems will not be graded! Once you submit a regrade request due to a problem tagged incorrectly, there will be between 10 to 50% penalty for that problem (the penalty will progress, starting with Homework #2.)

An example of the PDF submission process is depicted in this video.

Note: It is also possible to choose to take a picture of each question and upload each question individually, though this is less recommended.

Gradescope has its own mobile app for submitting homework (though the website is still the only way to view feedback and submit online/timed assignments).

How do I produce a PDF of my homework?

This does not mean you have to do your homework on a computer. It just means you have to scan your handwritten work and create a PDF. The first thing to be aware of is that the scan will come out much better if you write in a darker pencil or pen.

To actually scan your homework, there are a number of mobile/tablet apps for various platforms recommended by Gradescope that will allow you to turn photos into multi-page PDFs. Note: GeniusScan is also available for iPhone and some may find it preferrable to Scannable.

Alternatively, there are traditional scanners in many (theoretically all) computer clusters in campus residences and many (theoretically all) campus libraries. Contact the Residential Computing help desk for details.

MOST IMPORTANT POINT: Make sure to preview your scan before you upload it to Gradescope! You want to make sure that every bit of work is visible and readable so that the graders can provide accurate feedback on your solutions.

What if I notice an error in my solution or forgot a page of my homework when I submitted it?

If the deadline has not passed, you can resubmit your homework. Simply go to Gradescope and click on the relevant assignment to view your submission. In the bottom right hand corner of your browser, you should see a "resubmit" button. This will allow you to update your submission to correct the error you noticed. Only your final submission will be graded.

Important note: Choosing to resubmit your assignment will completely erase your current submission, meaning you will have to reupload your entire solution again. Gradescope does not currently allow you to just update a single question.

How do I see how I did on the homework assignment?

Once the submission deadline has passed, your homework will be graded. This usually takes about a week. Therefore, around the following Tuesday, you will receive an email saying that your graded work is available for viewing. Your score as well as grader feedback on your homework will be available in Gradescope.


Autumn 2025
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