Table of contents

  1. Course Info
  2. Realistic Prerequisites
  3. Subject Matter
  4. Course Staff
  5. Lectures
  6. Problem Sets
  7. Exams
  8. Resources
  9. Grading
  10. Advice to Future Students

Course Info

Class Size 34
Hours/Week 11.3 (11 responses)
Instructors Xueying Yu (Lecturer), Cindy Y. Zhang (UA)
# of Responses to Course 18 Underground Questions 7/34

Realistic Prerequisites

  • 18.02 strongly recommended.
  • Prior proof writing experience also recommended.

Subject Matter

  • Theoretical with a few applied examples. Essential foundation for upper level math.
  • Students generally found the material interesting. Some students felt the material was presented too quickly.

Course Staff

  • Overwhelmingly positive. Students found the professor approachable, engaging, and caring.
  • “The professor is very helpful and emailed me personally to talk over the midterm. I appreciated her taking the time to talk with me, and I was not made to feel bad about my midterm grade, the meeting was purely to help my learning.”
  • “All professors and TAs went above and beyond to help me. They are the most caring, approachable and kind people. I cannot speak more highly of them.”


  • The lectures recieved mixed reviews. Some students felt that the lectures were too fast and assumed too much proof writing background, while others found the pace good.
  • Lectures were typically a repeat of proofs from the book.

Problem Sets

  • Assigned weekly.
  • Challenging but not too challenging.
  • The lectures prepared students for the problem sets. The problem sets were similar to problems covered in lecture.
  • Prepared students well for the midterm.


  • One 24-hour take-home midterm, worth 25% of the grade. The average was in the 60s.
  • Final exam was stressful, worth 25% of the grade.
  • Students found the exams difficult. Some felt that more exam practice could’ve been given.


  • The course used a free online textbook (Lebl - Basic Analysis: Introduction to Real Analysis (Vol. 1)), which students found very helpful.
  • Lecture notes were also available.


  • Grading was fair and transparent. Grading was lenient on the problem sets and tough on the exams.
  • “I am not too clear on the expected grade distribution, but I think the professor did say anything above an 85 - 90 is an A.”

Advice to Future Students

  1. “Ensure that you get some sort of background in proof-writing before taking 18.100A.”
  2. “Definitely recommend this class if you want a good foundation in proofs. Well-taught and enjoyable..”
  3. “If you lack the passion for math this will be a painful class. If you enjoy math this will be a gateway into a wonderful world.”
  4. “Read the textbook!”