Differentiate the following functions from first principles :
e–x
We have to find the derivative of e–x with the first principle method, so,
f(x) = e–x
by using the first principle formula, we get,
f ‘(x) = 
f ‘(x) = 
f ‘(x) = 
f ‘(x) = 
[By using 
= 1]
f ‘(x) = – e–x
1