2022 MGS AMath Prelims P2 Ans

2022 MGS A Math Preliminary Exam P2 Answer Key 1 (ii) radians/sec or -5.03 rad/s 2 (ii) 0.528 or 3 (a) (b) (i) (ii) a = 2, b = 25 4 (i) let (Tangent-Chord Theorem) (KD bisects ) (ii) ( are similar) (iii) (angle sum of triangle) (supp angle) - M1 (angle sum of triangle) - M1 (supp angle) since , is isosceles. - A1 5 (b) 6 7 (a) , since the minimum point is (1.5, 2.5), the graph lies above y = 2. (b) or (c) x = 4, y = 1 8 (b) (i) (eqn CE), (eqn DA) (ii) E (9, 0), (b) BCDE is a trapezium. BC is parallel to DE and (c) 78 units2 5 8p- 42e- 4320-2218 2 8 . . .ax a x++ + ,CAD xÐ= CAD ABC xÐ= Ð=ADH CDH yÐ= Ð= ADCÐHD AD KD BD = andAHD BKDDD HD BD KD AD´=´ 180AHD x yÐ= ° - - AHK x yÐ= + 180BKD x yÐ= ° - - AHK x yÐ= + AHK AKHÐ= ÐAHKD59, , 44 4 xppp= 22 74 2 3 2 (2 ) ( 5 ) 2 5 xx xx x x +- =+-+ - + 2 352 22 xæö-+ç÷èø 6561x=1 9 x= 2 6 3 yx=- + 59yx=- :1 : 2DA AE=BC DE¹

Page 2 of 20 Methodist Girls’ School Additional Mathematics Paper 2 Sec 4 Preliminary Exam 2022 9 (i) (ii) 2.20 10 (ii) (iii) max P = 38.6 cm when (iv) 11 (ii) , (iii) no. of weeks = 4.95 (iv) The model is based on exponential increase and the number of insects cannot increase indefinitely. In 5 years, it will have 4.40 x 1018 insects, which is impractical. 11 or 4 2 1 24 yx y x=- = - 19 386 cos( 14.7 )P q=+ - ° 14.7q=°63.3q=°1.52p= 765k=