Math With AmarA C A D E M Y

100 free lessons · Worked examples and practice

Undergraduate math

Explore selected university topics across proof, algebra, geometry, analysis, and probability. Each lesson offers a focused entry point with an explicit problem and a worked argument you can reconstruct.

An advanced mathematics workspace with geometric models and research notes
Use the pictures and worked reasoning as a starting point. Make your own sketch, explain your choices, and check the result.

Your study guide

What you will explore.

  • Read and construct mathematical arguments
  • Connect algebraic, geometric, and analytic viewpoints
  • Apply models while checking their hypotheses

Before you begin

There is no single linear prerequisite chain across all 100 lessons. Choose a subject you know, read its prerequisites, and review the necessary calculus, linear algebra, or proof techniques first.

Review Grade 12

How to study these lessons

Rewrite the argument without looking at the solution. Identify where each assumption enters, and try a small example or counterexample to test the boundaries of the claim.

Work at your own pace. Open a hint when you need it, then try again before revealing the complete explanation.

Grade labels are starting-point guides; school sequences vary. University lessons introduce selected topics and assume the prerequisites listed on each page.

Practice with a moving example

650 guided practice chapters for Undergraduate.

Try a distinct question, open a hint, compare the worked solution, and explore its interactive animation. These scenario chapters give you more practice within this level’s topics.

Open the practice collection

Learn with Amar

Teaching videos, chapter by chapter.

Teaching recordings for this level are being prepared. Browse the chapter index to see video availability and open the written lessons that are ready now.

Browse chapters and video availability

Learn one idea at a time

Your Undergraduate lesson collection.

The lessons appear in their suggested study order. Choose the first lesson for a starting point, or use the search and subject filters to review a particular skill. Read the prerequisites whenever you change topics.

Showing 12 of 100 matching lessons · All free

An advanced mathematics workspace with geometric models and research notesAlgebra

Undergraduate · Advanced 16 min

Why the order of quantifiers changes a claim

Distinguish a uniform choice from a choice that depends on the input.

Read, practice, and reflect
An advanced mathematics workspace with geometric models and research notesAlgebra

Undergraduate · Advanced 16 min

Build a strong-induction postage argument

Use several base cases to support a recurrence that moves by four.

Read, practice, and reflect
An advanced mathematics workspace with geometric models and research notesAlgebra

Undergraduate · Advanced 16 min

Compress integers into residue classes

Verify an equivalence relation and perform well-defined arithmetic on classes.

Read, practice, and reflect
An advanced mathematics workspace with geometric models and research notesAlgebra

Undergraduate · Advanced 16 min

Recover a greatest common divisor as a linear combination

Run Euclid's algorithm and reverse it to obtain Bézout coefficients.

Read, practice, and reflect
An advanced mathematics workspace with geometric models and research notesAlgebra

Undergraduate · Advanced 16 min

Undo multiplication modulo a prime

Find a modular inverse through a Bézout identity rather than trial division.

Read, practice, and reflect
An advanced mathematics workspace with geometric models and research notesAlgebra

Undergraduate · Advanced 16 min

Combine two independent remainder schedules

Solve simultaneous congruences and identify the repetition period.

Read, practice, and reflect
An advanced mathematics workspace with geometric models and research notesAlgebra

Undergraduate · Advanced 16 min

Reuse elimination with an LU factorization

Separate elimination from back substitution to solve repeated linear systems.

Read, practice, and reflect
An advanced mathematics workspace with geometric models and research notesAlgebra

Undergraduate · Advanced 16 min

Find all invisible inputs of a linear map

Parameterize a nullspace and connect free variables to lost information.

Read, practice, and reflect
An advanced mathematics workspace with geometric models and research notesAlgebra

Undergraduate · Advanced 16 min

Describe the same vector in another coordinate system

Solve for coordinates relative to a nonstandard basis.

Read, practice, and reflect
An advanced mathematics workspace with geometric models and research notesAlgebra

Undergraduate · Advanced 16 min

Turn differentiation into a matrix

Represent an operator using its action on basis vectors.

Read, practice, and reflect
An advanced mathematics workspace with geometric models and research notesAlgebra

Undergraduate · Advanced 16 min

Separate a signal from its perpendicular residual

Compute a least-distance projection onto a line.

Read, practice, and reflect
An advanced mathematics workspace with geometric models and research notesAlgebra

Undergraduate · Advanced 16 min

Create perpendicular directions without changing the span

Orthogonalize independent vectors by subtracting a projection.

Read, practice, and reflect