reunakäyrän

Reunakäyrä, often translated as "boundary curve" or "envelope curve" in English, is a concept found in mathematics and economics. In mathematics, a reunakäyrä refers to the envelope of a family of curves. This is the curve that is tangent to each curve in the family at some point. It represents the outer limit or boundary traced by these curves as a parameter changes. The mathematics involved in finding a reunakäyrä typically involves calculus, specifically finding where the partial derivative of the family of curves with respect to the parameter is zero.

In economics, the term reunakäyrä is often used in the context of production possibility frontiers (PPF) or utility possibility frontiers. A PPF illustrates the maximum output that can be produced with a given set of resources. When considering different levels of technology or resource allocation, the "reunakäyrä" can represent the set of all efficient production possibilities. Similarly, in the context of welfare economics and social choice theory, a utility possibility frontier shows the maximum attainable levels of utility for individuals given the total resources of a society. The reunakäyrä here represents the Pareto efficient allocations of utility. It signifies the point where it's impossible to increase one person's utility without decreasing another's.