A function between Spaces, Sets, and Objects

Injective

If there is at most one location in the Codomain for every location in the Domain

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Surjective

If there is a location in the Codomain for every location in the Domain

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Bijective

If there is exactly one location in the Codomain for every location in the Domain for the Transformation

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Linear Transformation

Linear Transformation

A Linear transformation is a Transformation where

  • where
  • Domain of T is (where we start)
  • Codomain or target of T is
  • The vector is the image of under T
  • The set of all possible images is called the range
  • image range codomain
  • When the domain and codomain are both , you can represent them as a Cartesian Graph in , as in a mapping of
    • If y is the codomain and x is the domain, the range is the range, the domain is all the images of f(x)
  • Addition Rule
    • T(u + v) = T(u) + T(v)
  • Multiplication Rule
    • T(c) = cT(v)
  • Prove a transformation is linear by proving the addition and multiplication rules.
  • “Principle of Superposition”
    • If we know , …, then we know every T(v)

1-1

Circular transclusion detected: Mathematics/SetTheory/Injective

  • 1-1 every column of T is a pivot column
  • 1-1 iff standard matrix has pivot in every column

Onto

Circular transclusion detected: Mathematics/SetTheory/Surjective

  • TLDR: Onto every row of T is a pivot row
  • onto iff the standard matrix has a pivot in every row
  • The matrix A has columns which span .
  • The matrix A has all pivotal rows.

Bijective

Circular transclusion detected: Mathematics/SetTheory/Bijective

  • Needs square matrix

Matrix Multiplication is a Linear Transformation

Compute

Calculate so that

Give a Give a that is not in the range of Give a that is not in the span of the columns of (Same question for all)

Range of is a bunch of images of the following form:

For to not be in the range of , it cannot be in the above form, e.g. it can be

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