Linear Algebra — Basic

Fundamentals of Vector Spaces, Eigenvalues, and Determinants (Undergraduate Level)

Overview

The basic level covers three core concepts of linear algebra: vector spaces, eigenvalues and eigenvectors, and determinants. These are fundamental tools used throughout modern mathematics.

Learning Objectives

  • Understand the abstract definition of vector spaces
  • Grasp the concepts of linear independence and basis
  • Learn the definition and computation of eigenvalues and eigenvectors
  • Master basic determinant computation methods (cofactor expansion, Cramer's rule)

Table of Contents

  1. Chapter 1 Fundamentals of Vector Spaces

    Axiomatic definition, beyond $\mathbb{R}^n$ — polynomials and functions as vectors

  2. Chapter 2 Linear Independence and Basis

    Linear combinations, linear independence, basis, dimension

  3. Chapter 3 Introduction to Determinants: Cramer's Rule

    Deriving the determinant from systems of equations — a historical approach

  4. Chapter 4 Determinants: Cofactor Expansion

    Cofactors, minors, Laplace expansion, inverse matrices

  5. Chapter 5 Visual Understanding of Determinants

    Shear transformations, parallelograms, changes in area and volume

  6. Chapter 6 Eigenvalues and Eigenvectors

    Definition, geometric meaning, characteristic polynomial, eigenspaces

  7. Chapter 7 Properties and Applications of Eigenvalues

    Trace and determinant, triangular matrices, linear independence, applications

  8. Chapter 8 Structure of Solutions of Linear Systems

    Homogeneous and non-homogeneous systems, solution space structure theorem, rank-nullity theorem

  9. Chapter 9 The Identity Matrix

    Definition and basic properties, eigenvalues, the identity element of matrix multiplication

  10. Chapter 10 The Kronecker Delta

    Definition of δ_ij, Einstein notation, foundations of tensor notation

  11. Chapter 11 Matrix Rank

    Definition of rank, pivot-based computation via row reduction, rank-nullity theorem, full-rank equivalences. Appendix: Strang-style proof of row rank = column rank

  12. Chapter 12 Permutation Matrices

    Definition, orthogonality, determinant, relation to LU decomposition, symmetric group, applications

Prerequisites

  • High school-level vectors (arrow vectors, component representation)
  • Basic matrix operations (addition, multiplication, inverse)
  • Fundamental concepts of sets and mappings