## Analysis/Topology: Bounded and Totally Bounded Sets

Definitions Bounded set: Let <M,ρ> be a metric space. We say that the subset A of M is bounded if there exists a positive number L such that ρ(x,y)≤L  (x,y∈A) (Wikipedia) Diameter of a set: If A is bounded, we define diameter of A (denoted by diam A) as diam A=  ρ(x,y). If A is not…

## Puzzle: Finding a Bounded Continuous Function

Find a continuous, real-valued with its range contained in (0, 1).

## Puzzle: Finding Real Roots of an Equation

How many ways can we solve a simple quadratic equation?

## Illustrating Simple Variation Problem

Calculus of variations is a subject where you study the extrema (maximum or minimum) of a function of functions. We know that, to find the extrema (maximum or minimum) of a “functional” of the form we first identify and substitute in Euler Equation (Or sometimes called Euler-Lagrange Equation) to obtain a Ordinary Differential Equation, solving…