17. What is the equation of the tangent line to y = (Vx - 5) when x = 3? [4 marks] Y = ( J X 2- 5 ) y'= 18. The graph off (x) is shown right. Use the graph to determine the values of x for which f (x) = 0. [1 mark] w 3 -2 - 2 - 19. Use the FIRST PRINCIPLES DEFINITION of a LIMIT to determine the derivative of f (x) = \x - 1 [4 marks] lim