What is f+?

f+ generally refers to the limit of a function f(x) as x approaches a value from the right (or from above). It is often denoted as:

lim x→a+ f(x)

This concept is crucial in calculus and real analysis. It's particularly important when dealing with functions that are not defined at a specific point, or that have different behaviors approaching from the left and right. For example, piecewise functions often require examining both the left-hand limit and the right-hand limit to determine if the overall limit exists. If the right-hand limit (f+) and the left-hand limit (f-) are equal at a point, then the two-sided limit exists and is equal to their common value.

• To understand it more deeply, explore the concept of Limits.
• Understanding Continuity is also vital. The right-hand limit being equal to the function's value at the point is part of the condition for right-continuity.
• It's used in the context of Asymptotes, especially for vertical asymptotes where the function approaches infinity (or negative infinity) as x approaches a certain value from the right.