Question 3 [50 marks] a) A function is given below with unknown coefficients B and C: f(x) = 2x'+3x- -Bx+ C i ) Find the derivative function f '(x). (5 marks) ii) If the x coordinates of the turning points are: x = -2 and x=1, find the value of unknown coefficient B in the equation. (10 marks) iii) If the x and y coordinates of the turning points are: (-2, 21) and (1, -6), find the value of unknown coefficient C in the equation. (10 marks)