18.102: Introduction to Functional Analysis

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 35
Hours/Week 10.9 (16 responses)
Instructors Pavel Etingof
Overall Rating 6.0/7.0

Realistic Prerequisites

  • 18.100x is a hard prerequisite. Students recommend knowing some metric space theory, which is currently only taught in 18.100B/Q.
  • Students recommend knowing some linear algebra.

Subject Matter

  • Students felt like the subject matter was very theoretical, but there were some applications regarding differential equations at the end of the course.

Course Staff

  • Professor Etingof was very helpful in helping students work through questions.
  • Office hours were seen as very helpful when working through the problem sets.


  • Lectures were seen as repetitions of the notes, and were sometimes very confusing to students.
  • Watching the recordings of the lectures helped clear up confusion.

Problem Sets

  • Some psets were very challenging, some were more straightforward.
  • Students spent anywhere from 5 to 10 hours on each pset.


  • Exams were stressful, as there were only 80 minutes for 5 problems.
  • Students were given a set of midterm problems to help prepare, which were modified versions of what would appear on the exams.


  • Students used notes from Prof. Richard Melrose
  • Lectures were also recorded, so students watched them back to review material.


  • Grading was noted as fair and transparent.
  • Approximately 30% of the class receives an A, and over 80% of people get A’s and B’s.
  • Grading put a large emphasis on the final (45%).

Advice to Future Students

  1. ”Go to office hours - the professor is very helpful.”
  2. ”Don’t underestimate the material, but it will be very rewarding!”