Optimisation problems as an introductory tool to Calculus

This work arises from the shortcomings detected in new students entering engineering degrees. When studying Differential Calculus, it is common for teachers to introduce the subject of optimisation problems at the end of the course, as an exclusive application of this discipline. This proposal suggests its incorporation prior to the study of the concept of the derivative, studying the variation, with the implementation of technology and didactic situations, analysing the trajectory of the students from that point until culminating the investigation with the solution of the same problems from the point of view of Calculus. The results can be surprising.