
HW for 5/21
Posted by Allen Olsen on 5/21/2019Objective: Find equations for ellipses and circles.
For the following assignment, the tables at the bottom of pages 575 and 577 are useful.
HW: Sect. 8.2, pp. 582  84:
1  6; 21  31 (odd); 37, 39.

HW for 5/16 (A), 5/17 (D)
Posted by Allen Olsen on 5/17/2019HW for the weekend:
Carefully read example 5 on page 569, and then do problems 49 through 52 on page 571.
Read problem 63 on pages 571  72 about the design of a suspension bridge, and play with the parabola that is described in the problem. See if you can understand what the problem is asking. Or, if you prefer, try Problem 64 about a bridge arch. These problems are best done with several students together.
If you are having problems with 11  29, look at example 3 on page 568.
See you on Monday.

HW for 5/16
Posted by Allen Olsen on 5/16/2019For A block: I am out today. When your celebrating is done, now read the following:
Your classroom assignment today is to work constructively together to complete last night’s homework.
If some of you want to show your work on the board for others to see, that is fine. But the goal should be to get everyone to the point that all have finished that homework. I will ask to see your homework for a homework grade when I see you on Monday. If you don't use this time productively, I will mark you down for it. If you have difficulties, send me an email and I will do my best to help. I expect to be back tomorrow, so you could ask me questions then. But get this done. I don't want to hear that "I didn't get how to do the problem." You have a ton of resources  each other, me, the textbook  engage, persist, and you will be able to figure it out!
If you finish the homework from last night, you can start reading section 8.2 of the textbook, or work on the weekend homework below:
HW for the weekend:
Carefully read example 5 on page 569, and then do problems 49 through 52 on page 571.
Read problem 63 on pages 571  72 about the design of a suspension bridge, and play with the parabola that is described in the problem. See if you can understand what the problem is asking. Or, if you prefer, try Problem 64 about a bridge arch. These problems are best done with several students together.
If you are having problems with 11  29, look at example 3 on page 568.

HW for 5/15
Posted by Allen Olsen on 5/15/2019Objective: Find the vertex, focus, directrix and focal width of parabolas.
HW: Sect. 8.1, pp. 570  71:
1  10; 11  29 (odd). Use the diagram on page 565, and especially look at the tables at the bottom of pages 566 and 567.
If you get stuck on these problems, look in the TEXTBOOK and READ or SKIM Section 8.1 for the definitions of terms or for examples that can show you how to do these problems.

HW for 5/14
Posted by Allen Olsen on 5/14/2019Objective: Calculate inverse matrices using row operations.
HW: p. 558, Chapter 7 Review Exercises:
29, 30, and 32.

HW for 5/7
Posted by Allen Olsen on 5/7/2019Some announcements.
1. Tomorrow Juniors must be at the Mock Crash. If you are not a Junior, you need to come to class.
2. On Friday morning, D block will meet in Room 801, instead of our regular room. This is because part of the US History AP Exam will be given in Room 803.
3. The Chapter 7 quiz will be on Thursday for A Block, in Room 803, and on Friday for D Block, in Room 801. This is a noncalculator Quiz. If you are unable to take this quiz, you must make arrangements in advance with me, or possibly lose credit. in general, you have two days at most to make up a test that you miss.
4. Continue to study for the exam, doing the problems outlined in the previous posting.

HW for 5/6
Posted by Allen Olsen on 5/6/2019Objective: Prepare for Chapter 7 Quiz.
I announced this for Wednesday, but because of the Mock Crash that all Juniors must attend during the first three blocks on Wednesday, I will have to move this exam to Thursday (A Block) and Friday (D Block). Some of you also have AP exams this week. I will need you to take this test by Friday at the latest. If this is not possible, you need to contact me by email immediately and then talk to me facetoface before the exam is given to set a retake date.
HW: Ch. 7 Review exercises: be able to do problems in the following groups:
Group 1: matrix multiplication: problems 3  10
Group 2: Evaluating determinants: problems 13  14
Group 3: Reducing augmented matrices to row echelon form: 16  18
Group 4: Solving systems of equations using Cramer's Method: 19  22
Group 5: Solving systems of equations using Gaussian Elimination: 23  28
Group 6: Solving systems of equations using reduced row echelon form: 33  36.
These are the only problems you need to work on in the chapter review, but you need to be able to do them.
I'm telling you this because I noticed that some of you were doing problems involving matrix addition, or inverse matrices. You don't have to do these problems.

Posting for 5/2 (A) and 5/3 (D)
Posted by Allen Olsen on 5/2/2019Today we practiced evaluating determinants using the row operations from our previous work with Gaussian Elimination.
We calculated the values of the determinants in this worksheet. Make sure that you have completed all these problems before the next class.
Notice: There will be a test next Wednesday in class on Sections 7.1, 7.2, and 7.3.

HW for 5/1
Posted by Allen Olsen on 5/1/2019Objective: Apply row operations to determinants to evaluate them.
Today we learned that row operations can be applied to determinants, and have the following effects:
1. An operation like 3R_1 + R_2 → R_2 does not change the value of the determinant.
2. If you multiply a row by a number n: n·R_1 → R_1, this multiplies the value of the determinant by n, too.
3. If you swap any two rows: R_1 ↔ R_2, this multiplies the determinant by 1.
We will continue this discussion in the next class. Meanwhile, this is today's
HW: Sect. 7.3, p 546:
55  66.

HW for 4/30
Posted by Allen Olsen on 4/30/2019Objective: Refine your skills finding the row echelon form of the augmented matrices of systems of equations.
HW: Sect. 7.3, pp. 54546: 33  44 (note that 41 has no solution); 55, 57, 58.
I have written up two examples of what the end result of Gaussian Elimination is when (a) there are an infinite number of solutions, or (b) there is no solution. Check it out here.