tag:blogger.com,1999:blog-64576871670925567522017-09-07T20:21:05.122-04:00MathemapunditBeing a weblog devoted to a variety of topics. Including Mathematics. And Mathematical Finance. Sometimes with homework.D. Handronnoreply@blogger.comBlogger373125tag:blogger.com,1999:blog-6457687167092556752.post-38919786880402968762014-11-18T15:34:00.004-05:002014-11-18T15:34:55.082-05:0021-241: Online Assignment #13There was an error in the way Problem #5 was being graded on this week's assignment. I'm pretty sure I figured out the problem and fixed it. If it was giving you problems, give it another try.D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-38541577003656806502014-09-23T10:12:00.000-04:002014-09-23T10:12:47.161-04:0021-241: Week #5 Online AssignmentOne of the problems I'd included on this week's WeBWorK assignment (Problem 7) was not being scored correctly. I was not able to fix the problem, so I removed it from the assignment. When you look at it now, you will see there is no Problem 7. It jumps form Problem 6 to Problem 8. Do not be alarmed!D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-42995050867766777722014-09-11T13:52:00.000-04:002014-09-11T13:52:11.452-04:0021-241: Lecture 7On Wednesday, September 10, we discussed the "Geometry of Linear Systems of Equations." I devoted a significant amount of time to discussing the "Row Picture" and the "Column Picture." This terminology does not appear in our textbook. I found these ideas in a previous semester when we used <i>Linear Algebra and It's Applications</i> by Gilbert Strang as the textbook. This book is being used by another instructor this semester, so copies are floating around. The topics I discussed are in Section 1.2 of that book.D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-33625199064701885472014-09-11T13:47:00.002-04:002014-09-11T13:47:17.358-04:0021-241: Lecture NotesI've fallen a little behind in the lecture notes, but notes through Friday, September 5, are available on the Blackboard site.D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-66036225661251073592014-09-11T13:35:00.000-04:002014-09-11T13:35:34.584-04:0021-241: Lectures 4 and 5 - LogicAs you have seen, I referred you to this <a href="http://math.berkeley.edu/~hutching/teach/proofs.pdf">Introduction to Mathematical Arguments</a> for our two lectures on logic and proof. I wanted to point you toward <a href="http://zimmer.csufresno.edu/~larryc/proofs/proofs.html">this additional resource</a> for another view of the subject.D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-6654695526323111592014-08-26T21:12:00.002-04:002014-08-26T21:12:37.038-04:0021-241: Class NotesI've posted the notes from Lecture 1 on the Blackboard site. They are in the "Course Content" area. I'll try to get notes written for each lecture, but I can make no promises!D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-77852402365735572922014-08-25T15:33:00.000-04:002014-08-25T15:33:03.672-04:0021-241: Week #1<p>The assignemnts for <a href="http://www.math.cmu.edu/~handron/21_241/hw/hw1a.html">Week #1</a> have been posted on the <a href="http://www.math.cmu.edu/~handron/21_241/hw/hw1a.html">Schedule</a> page. Note that you will have to click through some links to get to the homework problems that are due on Friday. </p> <p>The textbook introduces the idea of a matrix slightly earlier than we will in class - only a day or two, but it makes a difference due to the timing of HW#1. The homework problems selected will not require you to think in terms of matrices. We'll save that for next week. </p>D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-74330001850896031842014-08-25T15:28:00.000-04:002014-08-25T15:28:17.764-04:0021-241: Lecture 1Today's lecture covered Section 2.1 in the text. As I mentioned in class, we will be covering topics in a different order that the textbook, and so at times topics will be mentioned in the text that we will not yet have discussed. You will note that in Example 2.6, the textbook introduces the idea of a matrix, which we will not use in class until Friday.D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-91121941992196713312014-08-25T15:24:00.002-04:002014-08-25T15:24:13.336-04:0021-241: Fall 2014Welcome to 21-241 Matrices and Linear Transformations for the Fall 2014 semester. I'll post information and updates about the course on this blog. The main source of information about the course is the <a href="http://www.math.cmu.edu/~handron/21_241/index.html">Course Home Page</a>, and in particular, the <a href="http://www.math.cmu.edu/~handron/21_241/index.html">Schedule Page</a>. There is a <a href="http://www.cmu.edu/blackboard/">Balckboard</a> site for the course, which will be used to record your grades, and distribute solutions.D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-601768496463405732013-09-03T16:34:00.000-04:002013-09-03T16:35:06.393-04:0021-260: Edits to Online Assignment #2<p>I need to make some comments and clarifications about this week's online assignment. </p> <ol> <li>First, you need to find a differential equation, but you do not need to solve it! Also, I give you information that leads to an initial condition. You should enter an initial value problem (i.e. a differential equation with an initial condition) as your answer. I've updated the question to reflect this.</li> <li>When I wrote this problem, I made a mistake that has caused the interest rates to be very small. That's okay, though. We can live with that. Also, I accidentally wrote "mayment" instead of "payment." Finally, the numerical value of <i>k</i> that you enter should be in units of [$ per year]. Your answer should be to the nearest dollar. Blackboard won't let me make these corrections/updates in the problem, though.</li> <li>This is a linear differential equation, which we will discuss in class tomorrow. If you work out the answer to 2 decimal places, you should be okay.</li> <li>Same as for problem 3.</li> </ol>D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-36041344935829805402013-08-27T15:07:00.000-04:002013-08-27T15:07:05.142-04:0021-260: Edits to Online Assignment #1<p>I've made a couple corrections to the problems on Wednesday's online assignment. I know some of you (75 according to Blackboard) have already attempted these problems, but I don't think should create too many problems. Here are the changes I've made: </p> <ol> <li>In problem #4, I've changed "dy/dx" to "dy/dt", since the variable on the right hand side of the equations is t, not x. </li> <li>In problem #5, I've changed "f(t)" to "f(x)", since the independent variable in the differential equations is x. </li> </ol>D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-54651959245424497942013-05-17T13:31:00.001-04:002013-05-17T13:31:14.815-04:0021-270: Final Wrap UpWell, I've submitted final grades to the SIO site. They should be available to you all now. The Grade Center on the Blackboard site has a column for your "Cumulative Averge," which agrees almost exactly with my spreadsheet. If you have turned in any late assignments this semester, your average on Blackboard will be slightly higher than it ought to be. You can compare your grades for the semester to this <a href="http://www.math.cmu.edu/~handron/21_270/270stats.html">page of statistics</a> for the course. D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-72168488371687998732013-05-17T11:18:00.001-04:002013-05-17T11:18:17.979-04:0021-241: Final Wrap-UpWell, I've submitted final grades to the SIO site. They should be available to you all now. The Grade Center on the Blackboard site has a column for your "Cumulative Averge," which agrees almost exactly with my spreadsheet. If you have turned in any late assignments this semester, your average on Blackboard will be slightly higher than it ought to be. You can compare your grades for the semester to this <a href="http://www.math.cmu.edu/~handron/21_241/241stats.html">page of statistics</a> for the course. D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-21496749962427610972013-05-07T16:05:00.001-04:002013-05-07T16:05:12.085-04:0021-270: Final Exam ReviewThe review page for the final exam has been posted. You can follow the link from the <a href="http://www.math.cmu.edu/~handron/21_270/schedule.html">Schedule</a> page.D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-3826283375272888302013-04-30T21:24:00.000-04:002013-04-30T21:24:03.784-04:0021-241: Final Exam ReviewThe review page for the final exam has been posted. You can follow the link from the <a href="http://www.math.cmu.edu/~handron/21_241/schedule.html">Schedule</a> page.D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-86507798142815435862013-04-27T22:00:00.000-04:002013-04-27T22:00:11.548-04:0021-270: Week #15The reading and homework for Week #15 have been posted. You can follow the link from the <a href="http://www.math.cmu.edu/~handron/21_270/schedule.html">Schedule</a> page.D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-15541808506627550942013-04-26T22:24:00.000-04:002013-04-26T22:24:25.129-04:0021-241: Week #15The reading and homework assignments for Week #15 have been posted. You can follow the link from the <a href="http://www.math.cmu.edu/~handron/21_241/schedule.html">Schedule</a> page.D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-61245110577042836912013-04-25T14:13:00.002-04:002013-04-25T14:13:21.448-04:0021-270: Final Exam Conflicts<p>Students who have a conflict with the final exam, scheduled for Thursday, May 9, from 8:30-11:30am in UC McConomy, can take a makeup exam. The makeup exam will be given on Monday, May 13, from 5:30-8:30 in MM A14. The makeup exam is the same time and place as the 21-240 Final Exam. </p> <p>This exam is for students who have either a directly conflicting exam, or three exams beginning within a 25 hour period (one of them being the 21-241 exam). Students with a documented illness or University sponsored trip can also take the makeup. It is not a general alternate exam time. </p>D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-7724193874504844762013-04-25T14:11:00.000-04:002013-04-25T14:11:03.197-04:0021-241: Final Exam Conflicts<p>Students who have a conflict with the final exam, scheduled for Monday, May 6, from 8:30-11:30 in DH 2210, can take a makeup exam. The makeup exam will be given on Thursday, May 9, from 8:30-11:30am in UC McConomy. The makeup exam is the same time and place as the 21-270 Final Exam. </p> <p>This exam is for students who have either a directly conflicting exam, or three exams beginning within a 25 hour period (one of them being the 21-241 exam). Students with a documented illness or University sponsored trip can also take the makeup. It is not a general alternate exam time. </p>D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-48307049911609448032013-04-20T18:37:00.005-04:002013-04-20T18:37:43.083-04:0021-241: Week #14The reading and homework assignments for Week #14 have been posted. You can follow the link from the <a href="http://www.math.cmu.edu/~handron/21_241/schedule.html">Schedule</a> page.D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-44691756522820575052013-04-20T18:37:00.001-04:002013-04-20T18:37:11.992-04:0021-270: Week #14The reading and homework assignments for Week #14 have been posted. You can follow the link from the <a href="http://www.math.cmu.edu/~handron/21_270/schedule.html">Schedule</a> page.D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-57342113631516927432013-04-11T16:59:00.003-04:002013-04-11T16:59:39.297-04:0021-241: Exam #3The review page for Exam #3 has been posted. You can follow the link from the <a href="http://www.math.cmu.edu/~handron/21_241/schedule.html">Schedule</a> page.D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-15041257215289364522013-04-09T17:10:00.000-04:002013-04-09T17:10:18.601-04:0021-241: Homework #12 typoThere is a misprint in one of the problems in the electronic version of the text. In the electronic version, problem 5.3.22 makes reference to the matrix "[.4 .2.6 .8]". This should be a 2x2 matrix with [.4 .2] in the first row, and [.6 .8] in the second row.D. Handronnoreply@blogger.com0tag:blogger.com,1999:blog-6457687167092556752.post-57345996303838479462013-04-07T13:34:00.000-04:002013-04-07T13:34:53.911-04:0021-270: Calculator DurabilityWell, if nothing else, at least you don't ever have to worry about your calculator <a href="http://www.businessinsider.com/22-products-that-last-a-lifetime-2013-3#my-trusty-ti-30-x-got-me-through-all-of-grades-six-to-12-and-im-still-using-it-in-college-on-the-same-battery-11">wearing out</a>!D. Handronnoreply@blogger.com1tag:blogger.com,1999:blog-6457687167092556752.post-46397375526233722222013-04-06T14:15:00.001-04:002013-04-06T14:15:25.348-04:0021-241: Week #12The reading and homework assignments for Week #12 have been posted. You can follow the link from the <a href="http://www.math.cmu.edu/~handron/21_241/schedule.html">Schedule</a> page.D. Handronnoreply@blogger.com0