Euclidean vector space is direct sum of subspace and orthogonal complement (theorem & proof & notes)
30:52
Oxford Linear Algebra: Direct Sum of Vector Spaces
13:15
Sums U+W and direct sums U⊕W of subspaces | definition, criterions, several examples
9:00
Orthogonal Complements
49:48
14. Orthogonal Vectors and Subspaces
27:53
Residue Theorem | Ultimate Guide (+several examples)
44:23
A Swift Introduction to Geometric Algebra
27:05
24 - Intersections and sums of subspaces
31:07