Linear Algebra

Study of vectors, matrices, and linear transformations.

Basic Concepts

Matrices and Matrix Arithmetic

What is a Matrix?

A matrix is a rectangular array of numbers arranged in rows and columns. Think of it as a table that helps organize numbers or equations!

Example of a matrix: \[ A = \begin{bmatrix} 1 & 2 \ 3 & 4 \end{bmatrix} \]

Matrix Operations

  • Addition: You can add matrices of the same size by adding their corresponding elements.
  • Multiplication: Multiplying matrices is a bit trickier. You multiply rows by columns and add the results.
  • Transpose: Switch the rows and columns of a matrix.

Why Learn Matrices?

Matrices are used to solve systems of equations, transform images, and more!

Try It Out

  • Add: \[ \begin{bmatrix} 1 & 2 \ 3 & 4 \end{bmatrix} + \begin{bmatrix} 5 & 6 \ 7 & 8 \end{bmatrix} \]
  • Multiply: \[ \begin{bmatrix} 1 & 0 \ 0 & 1 \end{bmatrix} \cdot \begin{bmatrix} 2 & 3 \ 4 & 5 \end{bmatrix} \]

Examples

  • Adding two \( 2 \times 2 \) matrices element-wise.

  • Multiplying a matrix by the identity matrix leaves it unchanged.

In a Nutshell

Matrices are grids of numbers that you can add, multiply, and use to solve equations.

Key Terms

Matrix
A rectangular array of numbers organized in rows and columns.
Transpose
An operation that flips a matrix over its diagonal, switching rows and columns.
Identity Matrix
A special matrix that acts like 1 in multiplication.