Last modified 20 December 2001 by

Math 221, Sections 390 and 391

  1. News
  2. Introduction
  3. Course Requirements and Grading
  4. Contact Information
  5. Getting Extra Help
  6. Exam and Quiz Results
  7. Take-Home Quizzes
  8. Writing Suggestions
  9. Study Guide
  10. Prof. Angenent's 221 Page with Homework Problems



Mathematics 221 is first-semester calculus. Our textbook is Calculus and Analytic Geometry by Thomas and Finney, 5th Edition. In this course we will explore the fundamental concept of limit and then use it to define derivative and integral, two of the most prevalent ideas in calculus. We will also learn a variety of techniques and applications.

Professor Angenent will lecture three days a week on new material, and I (your teaching assistant) will lead discussion on the other two days. In discussion sections, students will be expected to ask questions on homework and on concepts covered in lecture. Often the answers to these questions will come from other students. My job is to encourage participation and keep us on track. In short, "discussion" will be a discussion.

This web page will be updated frequently with class news, exam results, and other vaguely useful information. You will often find the answers to your class-related questions here. You will find additional, lecture-wide information at Prof. Angenent's 221 page.

Course Requirements and Grading

Your course grade will be computed from the following components:

In my class sections, the discussion component of the grade will be determined by short weekly quizzes. Some of these quizzes will take place in class, while others will be given as homework. The take-home quiz policy is explained in detail below.

If you miss a quiz, you will probably receive a grade of zero, unless there are extenuating circumstances. I am reluctant to give make-up quizzes. For this reason, you should come to discussion on quiz days. At the end of the semester, I will drop each student's lowest quiz score, so you can miss or fail one quiz without penalizing your grade.

Homework and attendance do not count toward your grade, but I hope you will show up to discussion ready to talk about homework problems anyway. You are encouraged to work on homework problems (but not quiz problems) with your classmates.

Contact Information

Here's how to get in touch with the lecturer:
Prof. Sigurd Angenent
Van Vleck Hall, Room 617
(608) 262-2883
Office hours Monday and Wednesday, 10:00-11:00, and by appointment
Here's how to get ahold of me:
Joshua Davis (call me Josh)
Van Vleck Hall, Room 518
(608) 262-3860
Office hours Monday 12:05-12:55, Wednesday 3:30-4:20, Thursday 1:20-2:10, and by appointment

If you can't attend my office hours, then consult my weekly schedule, pick an open slot, and make an appointment with me. If you have a quick question, then try catching me after discussion or lecture; I usually sit in the back of the room at lecture.

Getting Extra Help

I find it very helpful to talk to other people about mathematics. Get to know your fellow students; discuss concepts and practice problems with them. Also, visit the professor and me during office hours.

Even if you work diligently, it is easy to get lost in math courses, as I can testify. This is especially true in early calculus courses, where students with varying backgrounds and expectations are thrown together. If you do find yourself falling a little behind, consider these options for extra help:

Most importantly, if you're not understanding the material, then try to catch up as soon as possible. In math courses each concept builds on earlier ones, so it's important to understand the concepts as we go along.

Exam and Quiz Results

You might find the following data useful in estimating how well you are doing in comparison to your classmates. If you are worried about your progress, come talk to me as soon as possible.

Number of Students Receiving Each ScoreTotalMean
Exam 1My 2 Sections342856760221110104914.8
6 of 8 Sections811111518191415677632011144?
Approx. GradeABCDF
Exam 2My 2 Sections001024358942042004412.5
All Sections???????????????????

113 Sep1-7, 1-88.2
220 Sep1-106.9
327 Sep2-2, 2-36.0
44 Oct2-8, 2-57.6
518 Oct2-9, 2-10, 3-25.6
625 Oct3-68.2
71 Nov3-8, 3-98.7
88 Nov4-29.4
915 Nov4-3, 4-47.2
1029 Nov4-6, 4-77.7
116 Dec5-2, 5-36.4
1213 Dec5-4, 5-5?

Take-Home Quizzes

You will be taking several take-home quizzes this semester. I like these because some students only get a chance to show what they know when they are given enough time to relax. Take-home quizzes count equally with quizzes taken in class, but typically they will be longer and more difficult.

There are several rules that you must understand and obey. You may take unlimited time to complete your quiz, but it must be turned in at the start of class on the day due. You may not discuss the quiz in any way with anyone else until it is handed in. You may consult your class notes and our class textbook freely, but you may not consult any other books or papers or electronic resources. You may use any calculator that is allowed on the exams. (Calculators with computer algebra systems are forbidden.) Your answers should be written clearly and concisely in complete, meaningful English sentences, as described below.

I am trusting you to obey these rules. Cheating will not be tolerated. If you have any questions regarding the rules, or any questions regarding the statement of the quiz problems, e-mail me as soon as possible.

Quiz 2 (Due 20 Sep)

Let f(x) = x2 + x. It turns out that the limit, as x goes to 2, of f(x) is 6. I am asking you to prove this limit in the following two ways (neither of which is "plugging in"). (A) Prove this limit using an epsilon-delta argument. You might find Example 2 in 1-10 helpful. (B) Prove this limit in detail using Theorem 1 in 1-10. Every step should use one of the parts of the theorem; show every step, and explain which part of the theorem applies.

Quiz 4 (Due 4 Oct)

(A) Do Problem 29 in 2-5. (B) Let f(x) = x12, g(x) = x + 3, h(x) = 1/x, i(x) = 4x, and j(x) = sqrt(x) (that's the square root of x). First, write down the formula for the function f(g(h(i(j(x))))); then use the chain rule to find its derivative with respect to x. Remember to write up your work cleanly, in well-constructed English sentences.

Quiz 6 (Due 25 Oct)

There is only one problem: 3-6, #10. This problem is worth 10 points. Do not forget to check every possibility necessary to show that your answer is correct. (For example, do not just check where the derivative is zero but also where it's undefined, and also find and check the boundary points, and make sure your answer is indeed a local maximum using the second derivative or some other argument.) You can check your answer in the back of the book; this means that I am more interested in your detailed, thorough work than in the answer itself.

Quiz 8 (Due 8 Nov)

Do Problems 4 and 25 in 4-2. In Problem 25, note that the top of the fraction looks like the derivative of the the expression under the cube-root; this should lead you to the correct substitution. As always, you are required to write your answers in complete sentences, but now I am offering to proofread your papers (for English, not math) before you hand them in. Just visit me in my office hours or after the Wednesday lecture.

Quiz 10 (Due 29 Nov)

As before, I am offering to proofread your papers before you hand them in. (A) Do 4-6 #2. (B) Let f(x) = x3 + x2. First, compute the integral, from -2 to 1, of f(x) dx. Second, compute the area of the region enclosed by the graph of y = f(x), the x-axis, and the lines x = -2 and x = 1.

Quiz 12 (Due 13 Dec)

As before, I am offering to proofread your papers before you hand them in. Remember that you are not allowed to discuss the quiz with anyone else! Your two problems are 5-4 #8 and 5-5 #5.

Writing Suggestions

Since you have a lot of time to prepare your take-home quizzes, I expect a thorough, well-organized exposition of your answers. Each problem should be worked out in detail, showing all of the steps necessary to derive the answer. That is, your solution should be a sequence of English sentences, in which each sentence follows logically from the sentences before it. Consider the following excerpt:

limx2 = 9.
x -> 3
This is an English sentence; it reads, "The limit of x2, as x goes to 3, is 9." Note that it contains a verb ("=", pronounced "equals" or "is") and uses punctuation. Before submitting your paper, read it aloud like this, and make sure that it consists of a sequence of grammatically correct sentences with proper punctuation.

Even if your sentences are grammatical, they can be hard to read if, like the one above, they are written entirely in mathematical notation. To help your reader, begin your sentences with additional words that convey how the sentence connects to the one before it, such as "therefore", "thus", "so", "on the other hand", "however", etc.

You do not need to write whole paragraphs of text explaining your strategy, unless what you are doing is highly unusual and would be hard to understand without explanation. On the other hand, you should indeed write in paragraphs, as you do when writing an essay for an English class. Do not use bullets or arrows to organize your sentences. For example, let's say you were doing a max/min problem (from 3-6). We typically solve these by a sequence of steps:

  1. Model the problem as a function to be maximized or minimized on an interval.
  2. Check where the derivative is zero.
  3. Check where the derivative is undefined.
  4. Check the boundary of the interval.
  5. Compare your answers from steps 2, 3, and 4 to arrive at your final answer.
Thus it would be natural for you to organize your exposition into five paragraphs, one for each step, with the first paragraph introducing the problem and the fifth paragraph concluding it. (But please do not number your paragraphs!)

Finally, you should be sure to submit a clean copy of your solutions, without significant erasures, crossings-out, or scratch work. You will probably want to figure out the problem in your own style and then recopy your work onto a new sheet of paper, organizing your thoughts as you go.

To get a better idea of the kind of clarity and organization that I'm hoping for, read your calculus textbook! Notice how the authors write in complete English sentences, even though mathematical notation is present.

Study Guide

Check out my one-page summary of limits and continuity here (PDF, 46 KB).

You can also view my one-page summary of derivatives here (PDF, 50 KB).

Maximization and Minimization

Max/min problems are often presented as story problems, and many students have difficulty in translating the story problem into mathematical terms. To practice this skill, I recommend that you go through all of the story problems in 3-6. Don't solve them all; just interpret them to the point where you know the function you want to maximize (or minimize) and the interval.

Once the max/min problem is clarified into the form ``We want to maximize (or minimize) f(x) on the interval [a, b],'' the solution becomes rather mechanical. You have to analyze all values of x where the derivative f'(x) is zero or undefined, and you have to check x = a and x = b. If you want to practice this skill, then you can again do book problems, but I have written a few extra ones where slightly unusual things happen:

  1. Maximize and minimize y = 4x2/3 - x8/3 on [-1, 1], [-2, 2], and [-3, 3].
  2. Maximize and minimize y = tan x on [0, pi/4] and [0, pi/2]. (Notice that tan x is undefined at pi/2.)
  3. Maximize and minimize y = x2/2 - |x| on [-1, 1] and [-2, 2]. (To differentiate |x|, you have to break it up into the x > 0 case and the x < 0 case.)