S B A D C Question 1. In the diagram above, the red curve is an arc of a circle centred at (0,0). In this question, we will prove that sin and cos are continuous. a) Using the diagram, show that sina a for 0 < a < 1. You may use the fact that a straight line provides the shortest distance between two points. b) Prove that lim sin h = 0. h0 c) Prove that lim cos h = 1. 0+4 d) Hence prove that sin and cos are continuous throughout their domain.