– This is the "gold standard" textbook. Chapters 5 and 6 cover Vector Calculus and Gradients specifically for ML [1].
Machine learning is primarily about finding patterns and minimizing errors. Calculus provides the language and tools to achieve this. calculus for machine learning pdf link
A derivative measures how a function changes as its input changes. In a machine learning context, if you change a model's weight by a tiny amount, the derivative tells you how much the model's error will change. dfdxd f over d x end-fraction – This is the "gold standard" textbook