Please help with the following questions

4. (a) (i) State the definition of the derivative of a function. 12 marks) (ii) Using the definition of part (i), find f'(x), when f(x) = V3r. (5 marks] (b) Prove that A (secr) = secr tant 15 marks] (c) Sketch the region bounded by the functions y = r and y = -1, then find its area. (7 marks) (d) Use the epsilon-delta (6 - 6) method to show that lim r'- r = 30. [6 marks]