Complex Integrals, Part 2: Complex-valued functions of a real variable
1 Introduction to Functions of Several Variables
FUNCTION OF TWO VARIABLE: LESSON 3 - LIMIT - PART 1
Pointwise Properties of Real Functions of a Single Real Variable
In mathematical analysis, and applications in geometry, applied mathematics, engineering, and natural sciences, a function of a real variable is a function whose domain is the real numbers ℝ, or a subset of ℝ that contains an interval of positive length. Most real functions that are considered and studied are differentiable in some interval.
The most widely considered such functions are the real functions, which are the real-valued functions of a real variable, that is, the functions of a real variable whose codomain is the set of real numbers.