9th edition vs 8th edition: You may use either edition, but if you choose to use the 8th, you should be aware of the following:

There are some changes to the text. A very brief description of these modifications can be found at http://www.wiley.com/WileyCDA/WileyTitle/productCd-EHEP000254.html

# For 22M:100 HW 10

Note section 5.5 in 9th edition = section 5.6 in 8th edition. Thus for 8th edition
HW 10 (due 4/17)
5.6: 7 (you must provide complete answers including induction proof and determine radius of convergence.)
7.4: 1, 5
7.6: 4, 10

There are very few changes with respect to the HW problems. For those who use the 8th edition instead of the 9th, you should be aware that

Section 3.3 in the 8th edition has been deleted. Hence
Section 3.4 in 8th = section 3.3 in 9th
Section 3.5 in 8th = section 3.4 in 9th,
Section 3.6 in 8th = section 3.5 in 9th, etc.

Section 5.4, 5.5 in 8th = section 5.4 in 9th
Thus in 8th edition do 5.5: 2, 3, 4, 7, 10 and 5.4: 8

Section 6.3 has 6 new HW problems.

If you plan to do extra credit problems from 6.3, e-mail me for conversion.

Hence from the 8th ed, do for Assignment 7 (due 10/22) 6.3: 5, 8, 9, 10, 13, 15, Also do problem 11 from 9th edition: (a) Sketch the graph of the given function. (b) Express f(t) in terms of the unit step function uc(t) where for problem 11: f(t) = t for 0 ≤ t < 1; t-1 for 1 ≤ t < 2; t-2 for 2 ≤ t < 3; 0 for t ≥ 3.

For Assignment 8: 6.3: 24, 25, 28, 29

Section 7.3 has 1 new HW problem. Hence from the 8th ed, do 7.3: 14, 15, 16

Note I may make minor changes to the above. Also if there are errors in my 8th to 9th edition conversion, please let me know.