Assignment:
Two mappings f: X→Y and g: X→Y are said to be equal ( and we write this f = g ) if f(x)= g(x) for every x in X. Let f , g and h be any three mappings of a non-empty set X into itself, and show that multiplication of mappings is associative in the sense that f(gh) = (fg)h.
Provide complete and step by step solution for the question and show calculations and use formulas.