Abstract
The exponential function and its defining base constant serve as fundamental pillars across real analysis and applied mathematics. This paper presents formal, step-by-step mathematical derivations of the foundational power-limit expressions for both the general exponential function and its base constant. Utilizing logarithmic transformations, continuity properties of elementary functions, and L'Hôpital's Rule for indeterminate forms of the one-to-the-power-of-infinity type, it rigorously resolves these limit identities. Additionally, this paper integrates a Maclaurin series expansion framework to demonstrate the direct analytical equivalence between limit-based definitions and infinite power series, unifying differential calculus and series representations.



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