We know that
$$ e^x=\sum_{n=0}^{\infty}\frac{x^n}{n!},x\in \mathbb R, $$
which can be written out $$ e^x=\frac {x^0}{0!}+\frac {x^1}{1!}+\frac {x^2}{2!}+\cdots, $$
but $0^0$ isn't well defined.
We know that
$$ e^x=\sum_{n=0}^{\infty}\frac{x^n}{n!},x\in \mathbb R, $$
which can be written out $$ e^x=\frac {x^0}{0!}+\frac {x^1}{1!}+\frac {x^2}{2!}+\cdots, $$
but $0^0$ isn't well defined.