Question 4 (a) (i) Let a > 0 and f: [0, a] - R be a continuous function. Show that Sof(x) dx = Sof(a - y)dy. (6 marks) (ii) Showing your working clearly, evaluate the integral VCOS X ONIA dx. vcos x +vsinx (6 marks) (b) Interpret 1-1 n lim 7-+00 n-+72 1=0 as a Riemann sum and evaluate it as a definite integral. (8 marks)