Question

Which type of graph will the function f(x) = e-x give?

Answer 1

is it `e` to the `-x` ? Like this, \(\normalsize\color{blue}{ f(x)=e^{-x}}\)

OR is it just \(\normalsize\color{blue}{ f(x)=e-x}\)

Answer 2

e is just a number, so when you say
\(\normalsize\color{blue}{ f(x)=e-x}\)
https://www.desmos.com/calculator/kcwgof1lkf

it would differ much from a plain \(\normalsize\color{blue}{ y=mx+b}\) which is a line
However, \(\normalsize\color{blue}{ f(x)=e^{-x}}\) would be \(\large\color{blue}{ f(x)=\frac{1}{e^{x}}}\) https://www.desmos.com/calculator/vctfh6dimo