Homework for Math 309A, Autumn 2012

There will be weekly homework assignments, usually but not always due on Wednesdays. Seven of the assignments will be collected and scored.

HW 1, Week 1 will not be collected or graded.
To prepare for the worksheet on Wednesday, be sure you know how to compute determinants, and review using row reduction to solve systems of linear equations. (For the latter, see Example 1, p. 375, or your linear algebra text.)
Do the following problems before the second week (so by 9/30). You can check your answers in the back of the book: §7.1: #2,3,6;§7.2: 1,4,8,10,14,16.

HW 2, due W 10/3 and all later assignments are at the 309 A, B&C Homework Page.

HOMEWORK FORMAT AND DEADLINES.

• Write your name, the class (e.g., Math 309A), the homework number, and the due date in the upper right corner of at least the front page of your homework.
• Don't be stingy with space. Leave at least one blank line between problems. If your writing shows through the paper, use only one side of the paper.
• Label every problem clearly.
• Show your work and/or reasoning. No credit will be given if all you show is the final answer given in the back of the book. More details about how much work to show are given below.
• STAPLE your pages together. The "fold and tear" method of fastening pages is not acceptable.
• No late homework will be accepted. If you believe this policy is not reasonable for you because of special circumstances, please see your instructor to discuss it.

HOW MUCH CALCULATION DO YOU HAVE TO SHOW?

• When computing a determinant or the roots of a polynomial, show clearly any work you did by hand (steps in multiplying, factoring or quadratic formula, etc.). If you use a calculator or program, state the start and finish of each calculation, and indicate the technology used. For instance, write down the matrix you need to take the determinant of, write down the resulting polynomial, write down the roots, and state the technology and/or program used.
• When solving a system of linear equations by row reduction, you do not have to reduce completely but may stop when the solutions are clear. For example, see the solution provided for Autumn 2011 Quiz 1, problem 1: the solutions are immediately clear without zeroing out the redundant line of each matrix or dividing to get leading coefficient = 1. You do not have to write down labels for every step of row reduction (e.g. "R₂ -> R₂ - 2 R₁") if you are sure it is very obvious what you did. But if you do several kinds of steps at once, make it easy for the grader to follow your work and say what you did. It might be a good idea to look over your work several hours later or the next day, to see how obvious your steps are. If you have to think hard to remember what you did in a step, you probably should give the grader more information.
• If you use a calculator or computer to do row reduction, show the initial matrix and the final matrix and say what technology and/or program you used to get the result.

Return to the Math 309A Homepage.
Most recently updated on September 30, 2012