Math 120 A - Spring 2018 - Dr. Matthew Conroy

Instructor:

Dr. Matthew Conroy

Office hours and email

TAs:

sections AA, AB

Joshua Southerland

jsouther (at) uw.edu

sections AC, AD

Mark Bennett

mbenn13 (at) uw.edu

Exam Dates:

Midterm 1: Thursday, April 19
Midterm 2: Thursday, May 17

Final Exam:
Saturday, June 2
5 to 7:50 PM
Location: Kane 110

June 8, 2018

Statistics for the final exam: n=109; min=2; 1st quartile=24; median=43; 3rd quartile=53; max=69.

Here is a histogram of scores on the final exam.

May 30, 2018

Here is an example showing the use of a sinusoidal function compared to a "linear" (really, "sawtooth" would be a better description) function in creating animations.

May 29,2018

To help you study for the final exam, here is a review sheet, and a list of some of the mechanical skills you will want to have well honed.

Comments on sinusoidal function work:

May 21, 2018

Midterm two statistics: n=118; min= 0; 1st quartile=15; median=25; 3rd quartile=32; max=40 (4 students).

Here is a histogram of midterm two scores.

May 13, 2018

NOTE: There will be no quiz section on Tuesday, May 15, due to a strike by at least some graduate student workers.

Midterm is Thursday, May 17. It will cover topics in Chapters 8 through 16. Here is a review sheet of the mechanical aspects of these topics.

When looking at old exams on the exam archive, keep in mind that some exams may cover topics in chapter 17, or chapter 7, which you will not be responsible for on your exam.

Here are some specific suggestions about old exams.

Please see below on this page (April 11, 2018) for my suggestions for how to study for exams. in this course.

April 25,2018

Petition forms for alternatives to the common final are available in the Mathematics Advising Office, C-36 Padelford (campus map) or online as a PDF, and should be filed by Friday, May 4 at 4:00 pm. You can read more here.

April 24, 2018

Here is plot of data from Math 120 A, Spring 2017. It shows course grade vs midterm one score. As you can see, a low score on the first midterm usually results in a quite low course grade. This plot does not include people who got a low score on the first midterm and then dropped the course.

April 24, 2018

Here is a scatter plot of midterm one scores versus total webassign homework scores (through chapter 7). It is interesting to note that, while having a high homework score appears not to be sufficient to do well on the midterm, it does appear to be more-or-less necessary.

April 23, 2018

First midterm exam statistics: n=127; min=0; 1st quartile=12; median=20; 3rd quartile =28; max=40 (1 student).

Here is a histogram of midterm one scores.

Here is a table of score-to-4.0-scale conversions. This is only to give you a rough idea of how you did on the exam: I do not use these converted values for any purpose.

≤130.0
140.7
151.0
161.3
171.7
182.0
192.4
202.7
212.8
222.9
233.0
243.0
253.1
263.2
273.3
283.4
293.5
303.5
313.6
323.7
333.8
343.9
354.0
364.0
374.0
384.0
394.0
404.0

April 15, 2018

Here is a review sheet covering the mechanical aspects of topics through Chapter 7.

April 14, 2018

One type of problem involving quadratic functions that you want to be able to solve is one in which we are given the value of an unknown quadratic function at three points and are asked to find the function. This is equivalent to knowing three points that the graph of an unknown quadratic function passes through. This is not too hard, but it helps to note that the algebraic steps always take the same form, and this let's us follow a similar process every time. Simply put, you will have three equations in three unknowns (a, b, and c), but subtracting any two of the equations eliminates c and so we can end up with two equations in two unknowns (a and b) very quickly. From there, there is not much keeping us from solving the problem (i.e., finding a, b, and c).

This is all illustrated in the handout Quadratic Function Algebra linked at right.

April 11, 2018

Suggestions for preparing for the midterm exam:

April 9, 2018

Comments on today's lecture:

April 3, 2018

CLUE Along with the Math Study Center, CLUE is an excellent resource I encourage all students of Math 120 to take advantage of. CLUE is a late-night drop-in study center on campus, and offers free tutoring for math, chemistry, physics, writing, and a number of other subjects. It is open 7-11pm Sunday through Thursday in the Mary Gates Hall commons. This quarter, CLUE also offers daytime math tutoring in the HUB Commuter & Transfer Commons on Wednesdays from 1-4pm. To learn more about CLUE you can visit CLUE's website.

Also, there will be Math 120 priority drop-in sessions. At a priority drop-in session, each of which will run 7-9pm, a math tutor will be designated to help specifically 120 students. (There will be a whiteboard just for 120 students to put their name on if they need help.) The students will be expected to come with questions; this isn't a formal exam review, but it's meant to give extra support to 120 students before their exams.

These sessions will occur on the following dates: Tuesday April 17
Tuesday May 8
Wednesday May 16
Thursday May 31

March 27, 2018

Algebraic sophistication: As I mentioned in lecture on Monday, an important thing for students in 120 to work on is what we might call algebraic sophistication. What I mean by this term is going beyond the point of just "getting by" when confronted with algebraic problems. Students need to become adept with their algebra skills, and be able to choose the best approach from a few possible options in their methods. Developing this sophistication will require paying attention to your algebra work and thinking about choices that you make when working problems, and noticing how certain choices lead to better outcomes than others. This is not easy, but it can make all the difference in whether or not a student does well in this course, and in calculus.

As an example of what I mean, every time I teach Math 120 I see students that, when they need to expand an expression like (x+2y)2 will apply the "foil" method, write (x+2y)(x+2y) = x^2+x(2y)+(2y)x+(2y)^2, etc. There is no question that this is correct. However, we encounter such expressions a lot; so often, in fact, that we should learn to use the identity (a+b)2 = a2+2ab+b2. With this, you can quickly expand (x+2y)2 = x2+4xy+4y2. Notice that this is identical to what you get when you "foil", but takes fewer steps and so is faster, but more importantly it is less likely to lead to an error (provided, of course, that you use the identity correctly).

There are many small things like this in our algebra work that can make a big difference in how quickly and how accurately we can solve problems (on exams, in particular, where time is limited, and you don't get multiple attempts as you do with the WebAssign homework). In lecture, I will be illustrating many of these methods: pay particular attention where I use algebra in a way that seems different from the way the you would. I will, as far as I am able, be showing you the shortest, safest, least tedious way to approach the algebra.

March 22, 2018

Welcome to Math 120 A Spring quarter 2018.

Announcements and other useful things will be posted here during the quarter.

Textbook: The textbook for this course is Precalculus, by Collingwood, Prince and Conroy. The book can be purchased at the UW Bookstore.

You do not have to purchase the textbook. It is available electronically: here is a direct link to the pdf.

Reading schedule: I have started a reading schedule (see the link at right) so you can stay on top of course topics, access all additional course materials, and get the most from lectures.

Discussion Board: The course has a discussion board (link at right). This is a great way to ask questions of me in a way that will benefit all students in the course. You can ask about homework questions, studying methods, etc. You can also use it to coordinate study sessions with other students.

Homework: We will be using WebAssign for homework.

WebAssign: You can log in to WebAssign here. This will require your UW Net ID. Your UW Net ID is the part of your university email address before the @ symbol. The password to log in is your UW Net ID password.

You must be enrolled in the course in order to get access to the homework on WebAssign.

You will need to purchase an access code before the grace period ends. You can purchase an access code on the WebAssign website after logging in.

The first homework assignment will be due on the night of April 3.

If you are not enrolled in the course, but are trying to add, you can get started on the homework without WebAssign by working the following problems in the textbook (which is freely available here).

Chapter 1: problems 1-10, 14,15
Chapter 2: 2-7, 10, 12, 13

These problems will have different numbers than the ones you will have on WebAssign, but if you write out solutions for these, it won't be too much trouble to rework them with the WebAssign values.

These problems will cover you through the first homework assignment.

I will periodically be expounding here on aspects of the course, particularly study methods and problem-solving tools.

Reading the problem This is an often overlooked key step in problem-solving. Be sure to always read the problem carefully, at least twice through before you begin solving the problem. A great way to fail to solve a problem is to attempt to solve a problem that wasn't asked, so make sure you are solving the problem you are given.

I think this is especially true during exams, where you cannot ask for help, or go away and come back to it the next day. So dedicate the first minute or two of work on each exam problem to reading slowly and carefully to be sure you are solving the right problem.

Introducing time variables We've seen in lecture that if an object is moving horizontally at a constant speed in the plane, then its location can be expressed by (A±vt,B), where (A,B) is the "starting location", v is the speed of the object, and t is the time since the object was at the starting location. That is, we are using t=0 to represent that starting time. The plus-or-minus depends on whether or not the object is moving to the right (minus) or left (plus).

A virtually identical method applies to objects moving vertically.

A common issue when using this method occurs when you have more than one object that don't all start moving at the same time. In such a case, you will need to adjust the expression above, keeping in mind that you want to multiply the speed v by the amount of time that the object has been moving since it was at its starting location. In general, this requires replacing t by t+a or t-a for some value of a depending on the start times of your objects.

Rounding and WebAssign In many problems in WebAssign, there is an instruction to round to a certain number of digits. PLEASE IGNORE THIS INSTRUCTION. Instead, keep all digits given by your calculator and enter all of them into WebAssign. I so often see students enter values like 46.5, get a red X, then enter 46.6, thinking that they have rounded wrong, and getting another red X, because their calculation was not correct. A better approach is to enter the full value you get from your calculator (46.51023923, say). In this example, this would still be marked wrong, but you wouldn't waste a second try messing with rounding. I promise that you will never be marked wrong for putting in "too many" digits.

WebAssign attempts For most problems, you have 5 attempts to enter the correct answer (the exceptions are mutliple choice and true-false questions). You should be very stingy about using these attempts. Do everything you can to check your work and your answer before using even the first attempt! Keep in mind that during exams you only get one attempt, so you want to be in the habit of checking your work yourself, and not just relying on WebAssign to tell you whether you have done things correctly.

Resources:

Handouts and Supplements

Other UW resources:

Math Study Center

Student Counseling Center

Information for Students of International TAs

Center for Learning
and Undergraduate
Enrichment (CLUE)