Differentiate each of the following functions from the first principal :
We have to find the derivative of 
with the first principle method, so,
f(x) = 
by using the first principle formula, we get,
f ‘(x) = 
f ‘(x) = 
f ‘(x) = 
f ‘(x) = 
[By using limx→0 
= 1]
f ‘(x) = 
[Rationalizing]
f ‘(x) = 
f ‘(x) = 
[sinA cosB – cosA sinB = sin(A–B)]
f ‘(x) = 
[By using limx→0 
= 1]
f ‘(x) = 
f ‘(x) = 
7