Differentiate the functions with respect to x.

cos(√x)

Differentiate the functions with respect to x.

cos x³ . sin² (x⁵)

Differentiate the functions with respect to x.

Prove that the function f given by f (x) = | x – 1|, x ∈ R is not differentiable at x = 1.

Prove that the greatest integer function defined by f (x) = [x], 0 < x < 3 is not differentiable at x = 1 and x = 2.