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Some formal analogies between the Differential Calculus in One Variable andthe Differential Calculus in Several Variables are presented. It is studied andintroduced the derivability of functions at several variables from the singlevariable conceptual analogous. This is obtained from exploring the dynamicimage of limit of a family of slopes of secants planes to the graphic of abivariate function.

La derivada en varias variables como analog\'ia formal de su hom\'onima escalar