Answer:
Exponential function if the form
is the constant multiple K of itself if.

Explanation:
The exponential function of the form
is the function which is the derivative of itself.
Where:
x is independent variable
Now if we talk about constant then again exponential function if the form
is the constant multiple K of itself if we take the dervative.
Mathmatical Prove:
Consider the general equation
let

Where:
K is a constant
c is the cofficient(could be any number)
Now:
Taking derivative of above equation w.r.t x:

Hence proved exponential function is a constant multiple K of it self.