Let f and g be functions Their sum denoted by (f+g)(x), is the function denoted by (t + g)(x) = f(x) + Their difference denoted by (f - g)(x), is the function denoted by it-gx) = f(x4-97 Their product denoted by (fog)(x), is the function denoted by. (19)*) = ) Their quotient denoted by () (), is the function denoted by 9) (*) = ke x The composite function denoted by (fºg) is defined by (f.g) (x) = f(g(x1). The piones of obtaining a composite function is called function composition.​