Lecture
This lecture covers the concept of partial derivatives and differentiability, focusing on the existence of partial derivatives at a point. It also discusses the differentiability of functions and the concept of limits in various contexts. The lecture further explores the solutions of differential equations, including homogeneous and non-homogeneous equations, and the use of initial conditions to determine coefficients. Additionally, it delves into the properties of sets in different spaces, such as open, closed, bounded, and unbounded sets. The lecture concludes with a discussion on local extrema and the verification of local maximum and minimum points in functions.