Exponential of Zero/Proof 3

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Theorem

$\exp 0 = 1$


Proof

This proof assumes the power series definition of $\exp$.

That is, let:

$\ds \exp x = \sum_{k \mathop = 0}^\infty \frac {x^k} {k!}$


Then:

\(\ds \exp 0\) \(=\) \(\ds \sum_{k \mathop = 0}^\infty \frac {0^k} {k!}\)
\(\ds \) \(=\) \(\ds 1\) Definition of Power of Zero

$\blacksquare$