# A calculus problem by j Joseph

Calculus Level 2

$\large \sum_{k=0}^\infty \dfrac{i^k}{k!} = \, ?$

Clarifications:

• $$i=\sqrt{-1}$$.

• $$!$$ denotes the factorial notation. For example, $$8! = 1\times2\times3\times\cdots\times8$$.

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