Introduction to Linear Algebra  (Spring 2024)

(Math 221, MWF 10:00-10:50AM, Neckers 218)

Instructor:  Dr. Dashun Xu

Office: 273 Neckers Hall A Wing
Office Hours: MW 8:50-9:55am, 11:00am-11:50pm, F: 8:50-9:55am, Th: 2-2:55pm, or by appointment

E-mail: dashunxu@siu.edu  Phone: 453-6598

Tutoring sessions: Lib 680 Mon-Thurs. from 5-9 -p.m

Important dates:

 Semester Classes Begin Tuesday, January 16 Last Day to Register Sunday, January 21 Last Day to drop w/ Reg. Office Friday, January 26 Last Day to Drop with Refund Sunday, January 28 Spring Break Sat, March 9-Sun, March 17 Last Day to Drop w/o Refund Friday, March 29 Total Solar Eclipse (Classes Cancelled) Monday, April 8 Final Examinations Mon, May 6-Fri, May 10 Commencement Saturday, May 11

 90   A 80   B 70   C 60   D 59   F

 Midterm exams 35 Homework 25 Final 32 Attendance (deduct 1 point per missed class meeting) 8

All assignments will be collected every Fridayin class and only a few questions in each assignment will be graded. Late homework will not be accepted. I will update these problems after each class meeting. Please make sure to refresh the webpage

 Homework Week 1 Sect 1.1: 5, 7(c), 8(c) Week 2 Sect 1.2: 2, 3(a, c,d), 5, 9, 11, 19, 25, 27 Together with Week 1, Due on Fri.   Please donot forget to staple your homework sheets together.   This webpage is updated according to the lecture pace in the afternoon (after 2pm) on MWF. That is, you can get all HW due on each Fri till  Wed after 2pm. Week 3 Sect 1.3: 1(d, e),  2(b, c), 3(e. f), 5(a, b, d, e), 5(g, k),   Sect. 1.3:  11, 13(a), 15, 23, 29(a,b) Week 4 1.4: 9, 12, 13, 15, 17, 20c, (using inverse 25, 27),  TF(a-k)    1.5: 2, 5(c), 6(b), 7, 8(ac), 11, 13, 15, 17, 19, 20, TF(a-g)   1.6: 1, 3, 5, 7, 9,   1.6: 13, 15, TF(a-g) Week 5 1.6: 11, 14, 16, optional: 18   1.7: 3, 9, 15, 19, 21, 27, 35(b), TF(a-m)   2.1: 1, 5, 17, 18, 19(a,b), 27, 29, 31 Week 6 2.2: 6, 7, 11, 15, 17, 18, 19, 21, optional (23, 25,27, 29, 30 )   2.3: 7, 15, 17, 19, TF (a-l) 2.3: 25, 33;   Review Problems: 1.2: 11, 25, 27 1.4: TF(a—g) 1.6: TF(a—f) 1.7: TF(j—m) 2.1: 21, 22, 2.2: 15--22 2.3: 19, 21, Homework are also collected on Fri.   Exam on Fri!!! Covering Chap1 and 2, including HW for 2.3 this week. Week 7 3.1: 1(a), 3, 11(a,c), 19   3.2: 1(b), 5(a), 9(a), 19, Week 8 3.2: 11(a), 3.3: 1cd, 3, 7, 8, 10, 13b, 19   4.1: 8, 11,  TF a-e. Week 9 4.2: 1(b, c,e); 2(a, d,f); 4(a,d), 5(a, b,c)   4.2: 7, 9, 11, 12(a,c), 17 Week 10 4.3: 1(a,b, d), 2, 3, 9   4.4: 2, 11(a), 13(a), 14, 19(a, b, d), TF(a-d) Week 11 4.4: 7 4.5: 1, 3, 4, 5   4.5:  12a, 15, 17, 19a 4.6: 1(abc), 3(ab); optional: 6, 12 Week 12 4.6: 9(abd) 4.7: 2(a), 9, 11, 12, 14, 15, 17 Week 13 HW: 4.7; 3a, 7b, 4.8: 2b, 5, 4.8: 1, 3, 6     Review: 4.2: 11, 12(ab) 4.3:2b, 3b 4.4: 13a, 19ab, 4.7: 9,  15, 16, 17 Exam on Next Wed.!!!   HW is collected on Fri.!!! Week 14 HW due on Fri. 5.1:  7, 12, 13, 5.2: 3, 6, 8, 9, diagonalize 13, 17 Exam on this Wed!!!   HW due on Fri. Review for the final: Week 7 and 13 homework and two review sets for midterm exams, together with 1.5: 11, 13, 2.3: 33, 34 4.2: 2(a, b, d, e) 5.2: 9, 11 Thm in 4.8   Review Lecture notes for chap6. Practice: 6.1: 29, 30, TF(a-f) 6.2: 1, 15, 16, 27 Final exam: 5/10, Fri. 10:15am - 12:15pm, NKRS 218

Study Hint:

Find at least one or two other students from the class with whom you can regularly do homework and prepare for exams. Your classmates are perhaps the least used and arguably your best resource. An efficient and effective study group will streamline homework and study time and greatly improve your written and spoken communication. The best time to use your classmates as study/homework partners is after you have made an honest effort on your own to solve the problems using your own wits, knowledge, and experience. When you encounter an unsolvable problem, don't give up too soon on it. Being stumped is an opportunity for mathematical growth and insight, even if you never solve the problem on your own. If you seek help prematurely, you will never know if you could have solved a tough problem without outside assistance.