Linear Algebra

Study of vectors, matrices, and linear transformations.
Basic Concepts

Vectors and Vector Spaces

What Are Vectors?

Vectors are mathematical objects that have both direction and magnitude. You can imagine a vector as an arrow pointing from one place to another in space. In math, we often write vectors as ordered lists of numbers, like \( \mathbf{v} = (2, 3) \) in two dimensions.

Exploring Vector Spaces

A vector space is a collection of vectors that you can add together and multiply by numbers (called scalars) to get new vectors. For a set to be a vector space, it must follow certain rules, such as:

  • Adding any two vectors in the space gives another vector in the space.
  • Multiplying any vector by a scalar (like 2 or -1) keeps it in the space.

Why Do We Care About Vectors?

Vectors are everywhere! They describe movement, forces, and even data in computer science.

Real-World Connections

  • Physics uses vectors to describe velocity and force.
  • Computer graphics use vectors to move and rotate images.

Operations on Vectors

  • Addition: \( (1,2) + (3,4) = (4,6) \)
  • Scalar Multiplication: \( 2 \times (1,2) = (2,4) \)

Working with vectors is like working with arrows—combine them, stretch them, or shrink them!

Examples

  • Adding the vectors (1, 2) and (3, 4) gives (4, 6).

  • Doubling the vector (2, -5) makes (4, -10).

In a Nutshell

Vectors have magnitude and direction; vector spaces are collections of vectors that can be added and scaled.

Key Terms

Vector
An object with both magnitude and direction.
Scalar
A real number used to scale vectors.
Vector Space
A set of vectors closed under addition and scalar multiplication.
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