if `f(x)=cosx` find `f' (x)` from the first principle and hence find `f'(pi/4)`

If f(x)=(x-1)^(2) , find f^(') from first principles.

If f(x) = x tan^(-1) x , find f'(1) from first principle.

If f(x) =(x-1)^2 , find f’ from first principles.

Find the derivative of f(x)=x sin x from the first principle.

Find the derivative of f(x)=sinx from the first principle.

Find the derivative of f(x)= xsin x from the first principle.

If f(x)=x tan^(-1)x, find f'(sqrt(3)) using the first principle.

Let the function f: QQ be defined by f(x)=4x-5 for all x in QQ . Show that f is invertible and hence find f^(-1)

Find from the first principle,the derivative of f(x)=sec2xat x=pi/8 .

If f(x)= sec 3x (x in R) , then find f'(x) by first principle.