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LIVE 125: Introduction

W 1–2am from 11/6 (Your Time*)

Enroll $439Full Course Details

This LIVE course contains a total of 20 hours of live video instruction (~$22/hour), plus 1 year of access to Prof. Loh's recorded videos from this course.

We’ve carefully designed our courses to maximize engagement. Each of our LIVE classrooms has at least one staff member for every 13 students. The typical class size is around 30 students.

* The official meeting time for this course is 8:00pm in New York.

The class time will change over the duration of this session, because your country's Daylight Savings Time adjustments differ from the target time zone of this course.

Diagnostic Tests:

Will I understand?Will I learn new things?

Calendar

Classes will meet on the highlighted dates. Click on any date to view the topics for that day.

Color Key:

Lesson on new topic

Discuss homework challenge

Nov 2024
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Dec 2024
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Jan 2025
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Apr 2025
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Reviews

YH

Very good, I like it very much, it’s the most fun class that I learn

SL

NUUUUUUUUUUUUUUUUUUUUUUUUU I DONT WANT IT TO END. NO, NO, NO. I DON'T WANT TO LEAVE. I WANT TO STAY.

LH

Wow, this math is so beautiful and elegant! This is my favorite class♥️ It is the most awesome and fun math class ever

TW

I find it great! The teachers are amazing! They always explain. Also, they calmly point out mistakes and key points which are crucial in solving the problem.

LC

it was fantastic

PD

I love the lesson

RV

My son was very happy and he told me that he had learnt a lot of new things and new ways of thinking. He got really engaged, although, before starting the course, he would say "I don't want to study during my vacations"... Thank you for your leadership and educational skills during the Module 0 course that my son took during the past 4 weeks.

AD

it’s really a wonderful class

JL

Its easy to follow. I like the videos

KH

My daughter has enjoyed this class very much and is planning to take further classes with “LIVE” in the fall. Both of the instructors are doing an amazing job!

MM

This is complicated but interesting at the same time

WM

This is the coolest prof ever

CZ

Thank you so much for the detailed and insightful feedback you provided for this course. Your thorough analysis and constructive suggestions were incredibly helpful and have given me a clearer understanding of the areas that need improvement.

CC

I think rat chelay is the best

YH

Very good, I like it very much, it’s the most fun class that I learn

SL

NUUUUUUUUUUUUUUUUUUUUUUUUU I DONT WANT IT TO END. NO, NO, NO. I DON'T WANT TO LEAVE. I WANT TO STAY.

LH

Wow, this math is so beautiful and elegant! This is my favorite class♥️ It is the most awesome and fun math class ever

TW

I find it great! The teachers are amazing! They always explain. Also, they calmly point out mistakes and key points which are crucial in solving the problem.

LC

it was fantastic

PD

I love the lesson

RV

My son was very happy and he told me that he had learnt a lot of new things and new ways of thinking. He got really engaged, although, before starting the course, he would say "I don't want to study during my vacations"... Thank you for your leadership and educational skills during the Module 0 course that my son took during the past 4 weeks.

AD

it’s really a wonderful class

JL

Its easy to follow. I like the videos

KH

My daughter has enjoyed this class very much and is planning to take further classes with “LIVE” in the fall. Both of the instructors are doing an amazing job!

MM

This is complicated but interesting at the same time

WM

This is the coolest prof ever

CZ

Thank you so much for the detailed and insightful feedback you provided for this course. Your thorough analysis and constructive suggestions were incredibly helpful and have given me a clearer understanding of the areas that need improvement.

CC

I think rat chelay is the best

YH

Very good, I like it very much, it’s the most fun class that I learn

SL

NUUUUUUUUUUUUUUUUUUUUUUUUU I DONT WANT IT TO END. NO, NO, NO. I DON'T WANT TO LEAVE. I WANT TO STAY.

LH

Wow, this math is so beautiful and elegant! This is my favorite class♥️ It is the most awesome and fun math class ever

TW

I find it great! The teachers are amazing! They always explain. Also, they calmly point out mistakes and key points which are crucial in solving the problem.

LC

it was fantastic

PD

I love the lesson

RV

My son was very happy and he told me that he had learnt a lot of new things and new ways of thinking. He got really engaged, although, before starting the course, he would say "I don't want to study during my vacations"... Thank you for your leadership and educational skills during the Module 0 course that my son took during the past 4 weeks.

AD

it’s really a wonderful class

JL

Its easy to follow. I like the videos

KH

My daughter has enjoyed this class very much and is planning to take further classes with “LIVE” in the fall. Both of the instructors are doing an amazing job!

MM

This is complicated but interesting at the same time

WM

This is the coolest prof ever

CZ

Thank you so much for the detailed and insightful feedback you provided for this course. Your thorough analysis and constructive suggestions were incredibly helpful and have given me a clearer understanding of the areas that need improvement.

CC

I think rat chelay is the best

YH

Very good, I like it very much, it’s the most fun class that I learn

SL

NUUUUUUUUUUUUUUUUUUUUUUUUU I DONT WANT IT TO END. NO, NO, NO. I DON'T WANT TO LEAVE. I WANT TO STAY.

LH

Wow, this math is so beautiful and elegant! This is my favorite class♥️ It is the most awesome and fun math class ever

TW

I find it great! The teachers are amazing! They always explain. Also, they calmly point out mistakes and key points which are crucial in solving the problem.

LC

it was fantastic

PD

I love the lesson

RV

My son was very happy and he told me that he had learnt a lot of new things and new ways of thinking. He got really engaged, although, before starting the course, he would say "I don't want to study during my vacations"... Thank you for your leadership and educational skills during the Module 0 course that my son took during the past 4 weeks.

AD

it’s really a wonderful class

JL

Its easy to follow. I like the videos

KH

My daughter has enjoyed this class very much and is planning to take further classes with “LIVE” in the fall. Both of the instructors are doing an amazing job!

MM

This is complicated but interesting at the same time

WM

This is the coolest prof ever

CZ

Thank you so much for the detailed and insightful feedback you provided for this course. Your thorough analysis and constructive suggestions were incredibly helpful and have given me a clearer understanding of the areas that need improvement.

CC

I think rat chelay is the best

YH

Very good, I like it very much, it’s the most fun class that I learn

SL

NUUUUUUUUUUUUUUUUUUUUUUUUU I DONT WANT IT TO END. NO, NO, NO. I DON'T WANT TO LEAVE. I WANT TO STAY.

LH

Wow, this math is so beautiful and elegant! This is my favorite class♥️ It is the most awesome and fun math class ever

TW

I find it great! The teachers are amazing! They always explain. Also, they calmly point out mistakes and key points which are crucial in solving the problem.

LC

it was fantastic

PD

I love the lesson

RV

My son was very happy and he told me that he had learnt a lot of new things and new ways of thinking. He got really engaged, although, before starting the course, he would say "I don't want to study during my vacations"... Thank you for your leadership and educational skills during the Module 0 course that my son took during the past 4 weeks.

AD

it’s really a wonderful class

JL

Its easy to follow. I like the videos

KH

My daughter has enjoyed this class very much and is planning to take further classes with “LIVE” in the fall. Both of the instructors are doing an amazing job!

MM

This is complicated but interesting at the same time

WM

This is the coolest prof ever

CZ

Thank you so much for the detailed and insightful feedback you provided for this course. Your thorough analysis and constructive suggestions were incredibly helpful and have given me a clearer understanding of the areas that need improvement.

CC

I think rat chelay is the best

YH

Very good, I like it very much, it’s the most fun class that I learn

SL

NUUUUUUUUUUUUUUUUUUUUUUUUU I DONT WANT IT TO END. NO, NO, NO. I DON'T WANT TO LEAVE. I WANT TO STAY.

LH

Wow, this math is so beautiful and elegant! This is my favorite class♥️ It is the most awesome and fun math class ever

TW

I find it great! The teachers are amazing! They always explain. Also, they calmly point out mistakes and key points which are crucial in solving the problem.

LC

it was fantastic

PD

I love the lesson

RV

My son was very happy and he told me that he had learnt a lot of new things and new ways of thinking. He got really engaged, although, before starting the course, he would say "I don't want to study during my vacations"... Thank you for your leadership and educational skills during the Module 0 course that my son took during the past 4 weeks.

AD

it’s really a wonderful class

JL

Its easy to follow. I like the videos

KH

My daughter has enjoyed this class very much and is planning to take further classes with “LIVE” in the fall. Both of the instructors are doing an amazing job!

MM

This is complicated but interesting at the same time

WM

This is the coolest prof ever

CZ

Thank you so much for the detailed and insightful feedback you provided for this course. Your thorough analysis and constructive suggestions were incredibly helpful and have given me a clearer understanding of the areas that need improvement.

CC

I think rat chelay is the best

YH

Very good, I like it very much, it’s the most fun class that I learn

SL

NUUUUUUUUUUUUUUUUUUUUUUUUU I DONT WANT IT TO END. NO, NO, NO. I DON'T WANT TO LEAVE. I WANT TO STAY.

LH

Wow, this math is so beautiful and elegant! This is my favorite class♥️ It is the most awesome and fun math class ever

TW

I find it great! The teachers are amazing! They always explain. Also, they calmly point out mistakes and key points which are crucial in solving the problem.

LC

it was fantastic

PD

I love the lesson

RV

My son was very happy and he told me that he had learnt a lot of new things and new ways of thinking. He got really engaged, although, before starting the course, he would say "I don't want to study during my vacations"... Thank you for your leadership and educational skills during the Module 0 course that my son took during the past 4 weeks.

AD

it’s really a wonderful class

JL

Its easy to follow. I like the videos

KH

My daughter has enjoyed this class very much and is planning to take further classes with “LIVE” in the fall. Both of the instructors are doing an amazing job!

MM

This is complicated but interesting at the same time

WM

This is the coolest prof ever

CZ

Thank you so much for the detailed and insightful feedback you provided for this course. Your thorough analysis and constructive suggestions were incredibly helpful and have given me a clearer understanding of the areas that need improvement.

CC

I think rat chelay is the best

YH

Very good, I like it very much, it’s the most fun class that I learn

SL

NUUUUUUUUUUUUUUUUUUUUUUUUU I DONT WANT IT TO END. NO, NO, NO. I DON'T WANT TO LEAVE. I WANT TO STAY.

LH

Wow, this math is so beautiful and elegant! This is my favorite class♥️ It is the most awesome and fun math class ever

TW

I find it great! The teachers are amazing! They always explain. Also, they calmly point out mistakes and key points which are crucial in solving the problem.

LC

it was fantastic

PD

I love the lesson

RV

My son was very happy and he told me that he had learnt a lot of new things and new ways of thinking. He got really engaged, although, before starting the course, he would say "I don't want to study during my vacations"... Thank you for your leadership and educational skills during the Module 0 course that my son took during the past 4 weeks.

AD

it’s really a wonderful class

JL

Its easy to follow. I like the videos

KH

My daughter has enjoyed this class very much and is planning to take further classes with “LIVE” in the fall. Both of the instructors are doing an amazing job!

MM

This is complicated but interesting at the same time

WM

This is the coolest prof ever

CZ

Thank you so much for the detailed and insightful feedback you provided for this course. Your thorough analysis and constructive suggestions were incredibly helpful and have given me a clearer understanding of the areas that need improvement.

CC

I think rat chelay is the best

YH

Very good, I like it very much, it’s the most fun class that I learn

SL

NUUUUUUUUUUUUUUUUUUUUUUUUU I DONT WANT IT TO END. NO, NO, NO. I DON'T WANT TO LEAVE. I WANT TO STAY.

LH

Wow, this math is so beautiful and elegant! This is my favorite class♥️ It is the most awesome and fun math class ever

TW

I find it great! The teachers are amazing! They always explain. Also, they calmly point out mistakes and key points which are crucial in solving the problem.

LC

it was fantastic

PD

I love the lesson

RV

My son was very happy and he told me that he had learnt a lot of new things and new ways of thinking. He got really engaged, although, before starting the course, he would say "I don't want to study during my vacations"... Thank you for your leadership and educational skills during the Module 0 course that my son took during the past 4 weeks.

AD

it’s really a wonderful class

JL

Its easy to follow. I like the videos

KH

My daughter has enjoyed this class very much and is planning to take further classes with “LIVE” in the fall. Both of the instructors are doing an amazing job!

MM

This is complicated but interesting at the same time

WM

This is the coolest prof ever

CZ

Thank you so much for the detailed and insightful feedback you provided for this course. Your thorough analysis and constructive suggestions were incredibly helpful and have given me a clearer understanding of the areas that need improvement.

CC

I think rat chelay is the best

YH

Very good, I like it very much, it’s the most fun class that I learn

SL

NUUUUUUUUUUUUUUUUUUUUUUUUU I DONT WANT IT TO END. NO, NO, NO. I DON'T WANT TO LEAVE. I WANT TO STAY.

LH

Wow, this math is so beautiful and elegant! This is my favorite class♥️ It is the most awesome and fun math class ever

TW

I find it great! The teachers are amazing! They always explain. Also, they calmly point out mistakes and key points which are crucial in solving the problem.

LC

it was fantastic

PD

I love the lesson

RV

My son was very happy and he told me that he had learnt a lot of new things and new ways of thinking. He got really engaged, although, before starting the course, he would say "I don't want to study during my vacations"... Thank you for your leadership and educational skills during the Module 0 course that my son took during the past 4 weeks.

AD

it’s really a wonderful class

JL

Its easy to follow. I like the videos

KH

My daughter has enjoyed this class very much and is planning to take further classes with “LIVE” in the fall. Both of the instructors are doing an amazing job!

MM

This is complicated but interesting at the same time

WM

This is the coolest prof ever

CZ

Thank you so much for the detailed and insightful feedback you provided for this course. Your thorough analysis and constructive suggestions were incredibly helpful and have given me a clearer understanding of the areas that need improvement.

CC

I think rat chelay is the best

YH

Very good, I like it very much, it’s the most fun class that I learn

SL

NUUUUUUUUUUUUUUUUUUUUUUUUU I DONT WANT IT TO END. NO, NO, NO. I DON'T WANT TO LEAVE. I WANT TO STAY.

LH

Wow, this math is so beautiful and elegant! This is my favorite class♥️ It is the most awesome and fun math class ever

TW

I find it great! The teachers are amazing! They always explain. Also, they calmly point out mistakes and key points which are crucial in solving the problem.

LC

it was fantastic

PD

I love the lesson

RV

My son was very happy and he told me that he had learnt a lot of new things and new ways of thinking. He got really engaged, although, before starting the course, he would say "I don't want to study during my vacations"... Thank you for your leadership and educational skills during the Module 0 course that my son took during the past 4 weeks.

AD

it’s really a wonderful class

JL

Its easy to follow. I like the videos

KH

My daughter has enjoyed this class very much and is planning to take further classes with “LIVE” in the fall. Both of the instructors are doing an amazing job!

MM

This is complicated but interesting at the same time

WM

This is the coolest prof ever

CZ

Thank you so much for the detailed and insightful feedback you provided for this course. Your thorough analysis and constructive suggestions were incredibly helpful and have given me a clearer understanding of the areas that need improvement.

CC

I think rat chelay is the best

YH

Very good, I like it very much, it’s the most fun class that I learn

SL

NUUUUUUUUUUUUUUUUUUUUUUUUU I DONT WANT IT TO END. NO, NO, NO. I DON'T WANT TO LEAVE. I WANT TO STAY.

LH

Wow, this math is so beautiful and elegant! This is my favorite class♥️ It is the most awesome and fun math class ever

TW

I find it great! The teachers are amazing! They always explain. Also, they calmly point out mistakes and key points which are crucial in solving the problem.

LC

it was fantastic

PD

I love the lesson

RV

My son was very happy and he told me that he had learnt a lot of new things and new ways of thinking. He got really engaged, although, before starting the course, he would say "I don't want to study during my vacations"... Thank you for your leadership and educational skills during the Module 0 course that my son took during the past 4 weeks.

AD

it’s really a wonderful class

JL

Its easy to follow. I like the videos

KH

My daughter has enjoyed this class very much and is planning to take further classes with “LIVE” in the fall. Both of the instructors are doing an amazing job!

MM

This is complicated but interesting at the same time

WM

This is the coolest prof ever

CZ

Thank you so much for the detailed and insightful feedback you provided for this course. Your thorough analysis and constructive suggestions were incredibly helpful and have given me a clearer understanding of the areas that need improvement.

CC

I think rat chelay is the best

Syllabus

The 20 course meetings are split in 16 lessons (called Day 1 through Day 16 below), and 4 homework exam discussions. Each exam discussion meeting happens after 4 lessons.

Day 1

Geometry: areas of plane figures; congruent triangles; Pythagorean Theorem

Day 2

Algebra; Geometry; Number Theory: area and volume of 3-D solids; prime numbers; prime factorization; systems of equations; transforming equations; square roots

Day 3

Combinatorics: permutations; exclusion; complementary counting

Day 4

Probability: counting; permutations; symmetry

Day 5

Logic; Algebra; Statistics: equations in one variable; arithmetic series; the substitution method; average; word problems

Day 6

Geometry: volume; similar figures; ratio and proportion; proportional lengths

Day 7

Number Theory: least common multiple; prime numbers; unique factorization

Day 8

Combinatorics: combinations; binomial coefficient identities; the multiplication principle

Day 9

Algebra: rate-time-distance problems; problem-solving using diagrams

Day 10

Geometry: circumference of a circle; irrational numbers; the distributive property; using equations to solve problems

Day 11

Probability: percents with applications; decimals; conditional probability; sets; total probability; equations in one variable

Day 12

Number Theory: word problems; parity; number of factors; prime factorization

Day 13

Geometry: angles of a polygon; sum of angles of a polygon; properties of parallel lines; interior and exterior angles;

Day 14

Algebra: reciprocals; sequences and series; factoring integers; least common denominator

Day 15

Combinatorics: counting; permutations; problem-solving using diagrams; linear recurrence relations; Fibonacci sequences

Day 16

Number Theory: Integers modulo m; square numbers; number sense techniques; variables

Co-Stars

Profile picture for Benny Wang
BENNY WANG

USAJMO Qualifier • HMIC Qualifier • USACO Gold • Enjoys writing math problems and playing piano

click for more

Profile picture for Allison Shen
ALLISON SHEN

Math Prize for Girls Qualifier • 3-Time AIME Qualifier • AMC 8 Perfect Score • School math club president • Indy Integirls Head Problem Writer • Indiana ARML A Team • Enjoys contemplating puzzles and books!

click for more

Refund Policy

No refund requests will be accepted after the student’s second LIVE session starts; Refund amount: 75% refund in the original payment method or 100% refund in course credits.