To students of AM 105a:

On 26 October 2007, Albert Tsou sent in the following Q & A.

Q: Why did the mathematician name his dog "Cauchy"?
A: Because the dog left a residue at every pole.

As you know, certain sections in Saff and Snider upset me, and I have deviated from the book. We all agree that no text should be held as an authority. But now, both you and I are paying for the deviation.

The notes here follow closely my lectures. Several students have mentioned that their own notes may reproduce what was written on the blackboards, but not what I said in class, so that they found it hard to reproduce the ideas.

In today's class of complex analysis, my co-instructor Scott Norris was lecturing on resonance.  He mentioned a YouTube video of the Tacoma Narrows Bridge.  Also instructive is the entry of the bridge on Wikipedia. 

Michael Brenner has just pointed out to me this video of the Moebius transformations.

I'm teaching Applied Mathematics 105a this semester.  The main content of the course is complex analysis.  The course is taken mainly by undergraduate students in Engineering, Physics, and Applied Mathematics.  There are about 70 people in the class, which makes it the largest class I have taught in the last 10 years. I have never taught a course on complex analysis before, but have used complex analysis in my research, and have taught the method of complex variables in my graduate course on elasticity.

This semester I'm teaching an undergraduate course on functions of a complex variable.  A student has just sent me a message:

Q: Why did the mathematician name his dog "Cauchy"?
A: Because the dog left a residue at every pole.

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I received an email several weeks ago with the following quote: