An exponentially increasing function, in the constant-rate exponential growth model, has the form
where
and
are constants. Its derivative satisfies
(Strang and Herman 2016). The prototypical example
is the exponential function
, plotted above.
Growth faster than every polynomial does not by itself imply exponential growth. For example, grows faster than
for every fixed
as
,
but more slowly than
for every fixed
.