Algebraic construction of homology and cohomology theories, aimed at applications to topology, geometry, groups and rings. Special emphasis on hom and tensor functors; projective, injective and flat modules; exact sequences; chain complexes; derived functors, in particular, ext and tor.

Prerequisites: Mathematics 220A-B-C.

4

Units

Optional

Grading

1, 2, 3

Passtime

None

Level Limit

Letters and science

College
ZHAO XIAOLEI
Xiaolei Zhao
3.7
12 reviews
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MATH 236A Huisgen-Zimme Winter 2023 Total: 15
MATH 236A Goodearl K Fall 2020 Total: 20
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12
3.7
math117 . Zhao Xiaolei A Month Ago

Straight up just copied out of a textbook. He did not explain proofs well enough that made sense. i'd avoid him. grades on a curve cuz the tests make no sense. or maybe im just stupid...

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math117 . Zhao Xiaolei 2 Months Ago

Smart and handsome guy. Really into math stuff. But the grading is a bit harsh but luckily he curves the grades finally..

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math117 . Zhao Xiaolei 6 Months Ago

Don't take him. Final and midterm weight heavy, and the tests are hard. A lots of assignments have to do. 117 is stressful and the lecture is not helpful.

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147A . Zhao Xiaolei 6 Months Ago

Really helpful lectures, and he's good at answering questions. He didn't assign a ton of homework, but what he did assign was pretty hard so going to office hours was necessary for me. The tests were hard, but he graded and curved SUPER generously. Honestly nothing bad to say, I'd recommend him to anyone.

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math117 . Zhao Xiaolei 6 Months Ago

He only copy down the textbook on the whiteboard. test are difficult and tough grader, avoid him!!! I don't think he's aware that this is a summer course.

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MATH111ABC . Zhao Xiaolei 7 Months Ago

midterm/final average was low af. doesnt really teach and expects you to review stuff on your own. tests are difficult

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