\circThe \circ operator is used to denote function composition in mathematics. It is a binary operator that takes two functions, f and g, and produces a new function, denoted as f \circ g, which is defined by (f \circ g)(x) = f(g(x)). This operator is essential in various fields of mathematics, including calculus and algebra, where it is used to combine functions in a specific order.
Function composition of f and g.
(f \circ g)(x) = f(g(x))Nested function composition.
(h \circ (f \circ g))(x) = h(f(g(x)))Composition of three functions.
(f \circ g \circ h)(x) = f(g(h(x)))