Linear Algebra You’ll Actually Use: Part 1

Linear Algebra You’ll Actually Use: Part 1

Is “a quantity with magnitude and direction” still your go-to vector definition?

Because I still remember one of my classmates giving that exact answer in class with full confidence. From the way most of us learned it in school? Completely correct. But our professor looked at him the way recruiters look at “I’m passionate about technology.”

That’s when I realized something: in AI, people don’t just expect us to know abstract linear algebra concepts, they expect intuition and an understanding of how those concepts are actually used in machine learning (modern linear algebra) . Linear algebra existed long before AI, but modern computing made it incredibly powerful because computers are extremely efficient at matrix operations.

Let’s now build this intuition step by step, starting with the basics.

Scalar

Imagine I ask you only one question: “How many hours did you sleep yesterday?”