\imageThe \image command is used in LaTeX to denote the image of a function, which is the set of all output values it may produce. This is often used in mathematical contexts to describe the range of a function or the result of applying a function to its domain.
Image of a function f from real numbers to real numbers.
\image(f) = \{ y \in \mathbb{R} \mid \exists x \in \mathbb{R}, y = f(x) \}Image of a linear transformation T from vector space V.
\image(T) = \{ T(v) \mid v \in V \}Image of a function g from set X.
\image(g) = \{ g(x) \mid x \in X \}