Duke is a beast. I say this as one of his former students and because of what one of my friends who is taking a graduate course told me. He is one the smartest guys in the department. But he walks around without a care in the world, sporting his Hawaiian shirts, shorts, and even flip flops.

I took Math 32A (Multivariable Differential Calculus) with this professor Fall 08. I would say that it was a good choice. His teaching style I would say focuses on proofs. He proves a general case in class, explains the reasoning behind the proof and why it works and its importance, and for homework you do applications of the proven theorems or facts or cases. For some people, this style is great, while for others it is not. But that's basically what it is.

Like others have said, Duke allows for two grading schemes. He calculates both grades and gives you the higher. The first scheme includes homework (10-20%, I forget). And two midterms (20% each I'd say). And the final (rest of the percentage). His second scheme includes homework for the same percentage, one midterm for 20% (or somewhere around there), and the final for the rest of the percentage. This comes in useful if you happen to mess up on one of his midterms.

The mean for the first midterm was around 67%. The second midterm was 65%. The final was around 55% or 60%. He does curve, though.

If do end up taking Duke, and if you ever have the time, I would highly suggest attending one of his office hour sessions. He's a really nice guy to talk to, as well as being super helpful and amazingly smart without making you feel like an inferior little freshman.

Good guy he is, and not a bad professor. He speaks a bit softly but if you sit in the front it should be fine. His writing is very legible. Though he might not look back often when going through a proof, when he's finished he does ask to make sure that everyone followed. If you don't speak up at that time, well, then, how should he know that you didn't understand the proof?

Overall I'd recommend Duke to the people who would like an approach to 32A that's based on light proofs.

I liked Professor Duke. He is a great professor for your first quarter of math -- his exams are reasonable (about 65-70 mean), and his grading system is very fair (he allows one of the midterm to be discounted in you score better on the final). He also REALLY cares about the success of his students, often asking us what we thought after exams and lectures and helping us in whatever way he can.

I took Math 32A in Fall 2008 with Professor Duke and he is so awesome! He is such a nice guy, is concerned about his students, and also has a great sense of humor. However, his lectures do get very dry and boring at times. He really does try to help his students understand the concepts rather than just showing us examples and stuff on the board, even though that's probably what the students might have preferred. Instead, Professor Duke ends up spending 3/4 of lecture time doing proofs which probably 80% of the class doesn't understand or ends up not paying attention. However, I do appreciate his effort for trying to help us understand the conceptual ideas behind this course. Overall, I thought the course material was pretty fair (Lagrange Multipliers, the last section, could get pretty tricky though). Going to lecture isn't exactly necessary (I didn't go to a few lectures and still did fairly well in the class), but of course, it'll always help more if you do go. No harm done, right? :) The key to the class is probably your homework: Make sure you do your homework (and not just copy it from people the night before!) and make sure you understand it! Do lots and lots of practice problems--that's probably the best method in preparing for the midterms and finals. Knowing the concepts is a definite plus, but exposure to different types of problems will help prepare you for almost anything on the exams. Professor Duke's midterms were definitely do-able, but extremely tricky. Once you figure out the trick, then the solutions will easily come to you. If you don't, then you'll be sitting there for a VERY long time trying to figure the problem out... I didn't like how both of the midterms were 5 questions, 20 points each. If you mess up one problem, then you basically lose a huge chunk of your points. The final, 10 questions and 10 points each, was pretty difficult (with a 57 average), although there were a few 100's in the class, but those people are just too good! I think if you stay within the 70-100 range for both midterms and the finals, you should be able to do fairly well in the class. :) Overall, this course was definitely a good one, and hard work usually will pay off! Good luck!

Professor Duke speaks English. That right there is basically the only good thing that can be said about him.
His lectures are completely useless because he just does thirty minute long proofs (yes.. each lecture is only 50 minutes). I think that he really gets an adrenaline rush from them because once he starts he doesn't stop and most of the time he'll get into another way of doing the proof. Don't feel guilty about not going to lectures because learning from the book or TAs will do you more good.
His midterms are definitely not what I would describe as easy, but they are certainly doable. It's really all about finding the trick to each and everyone of his problems... and trust me they're hardly ever straight forward. The average on the first midterm was 66 and 64 on the second. The final is an absolute bitch which will make your head hurt for days. The average on that was a 57.
Overall, try not to take Duke.. he sucks. But if you end up with him it's not the end of the world.

To get an A: understand concepts very well, be able to visualize everything learned in class (ie be able to visualize space curves, planes, gradient vectors, etc), understand all of the homework problems, and have a good TA that gives you review problems.

The two midterms are very easy and straight-forward. 100's are easily attainable on them if you know your fundamentals and can do the homework (the midterms are less conceptual). The final is MUCH harder than the midterms, being more abstract and conceptual. You MUST know what the hell each formula that you learn means and WHY it works. If you can do that, you will be able to understand the abstract, off-the-wall problems that appear on the final.

Duke is terrible at reviewing before midterms/final. He basically leaves it up to the TA to do the reviewing. I did not go to office hours, but apparently he is very friendly, so maybe try going if you have trouble.

Overall, he was an OK professor. He teaches you the fundamentals of everything, but you must rely on yourself to explore further through homework and reading. Another thing that many people mention here is that he definitely wastes class time on useless proofs. I understand that he is trying to help us solidify our concepts, but the proofs are very abstract at times and don't help your understanding of anything.

Not a bad teacher at all. He's great at helping you to understand the material. His tests are very fair. He tends to prove every little thing, but just know the concepts and how to apply them and you're good to go.