Trigonometry

(2 marks) (b) (i) Find the perimeter of the sector OAB. (3 marks) (ii) The perimeter of the sector OAB is equal to the perimeter of a square. Find the area of the square. (2 marks) Answer: (watch for units – the diagram has lengths in cms.) a) sector area = 1/2 r2θ = ½ 100 0.8 = 40 sq. cms. b) i) The perimeter is the arc length, plus 2 radii. ................
................