GraphMath

The four subspaces

Row, null, column and left null spaces

This chapter develops the four fundamental subspaces associated with a matrix A. It connects the algebraic definitions to geometric intuition, then relates the picture to Aᵀ and AᵀA.

Chapter contents

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Topic Pages
Definitions 1
The four subspaces of A: introduction 2–4
Geometric interpretation of the four subspaces of A 5–6
The four subspaces of A: summary table 7–8
Geometric view of transformations by A, Aᵀ & AᵀA 9–10
The four subspaces of Aᵀ 11
The four subspaces of AᵀA 12–13
Why do we need this abstract concept? 14–16
Tying it all together 17–18

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