Matrix with zero columns multiplied by vector with zero elements yields vector

[matthias314]

@Benny

Wouldn’t that be a map from \mathbb{R}^2 to \mathbb{R}^1

For any m and n there is a zero map \mathbb{R}^m\to\mathbb{R}^n because any vector space has a zero vector (generically written as “0”). In a 0-dimensional vector space, there are no other vectors. In other words, a 0-dimensional vector space is a single point (the origin).