Apps. and Interpretation for IBDP Maths Ebook 1 | Page 381

Answers 58.4 (a) x � 0 (b) 16 f �( x) � x � 3 x (c) (2, 4) (d) �1� x � 0 or x � 2 (e) (i) 8.5 (ii) 15 f �(4) � 4 (iii) 4 � 15 (iv) 4 287 y� � x� 15 30 (f) y � 4 Exercise 59 59.1 (a) (i) 2 27 � r h � 2r (ii) Refer to solution (b) dV 27 3 2 � � � �r dr 2 2 (c) 3 cm (d) (i) 3 27� cm (ii) 0 �V � 27� (e) 1.17 cm and 4.51 cm 59.2 (a) (i) (64 � 2 x) cm (b) (c) (d) (e) (ii) Refer to solution dV 2 12x 512x 4096 dx � � � 32 x � 3 (i) 3 19418 cm (ii) 0 �V � 19418 2 7280 cm 59.3 (a) (i) Refer to solution (ii) Refer to solution (b) dV 25 3 3 r dr 3 8 (c) r � 6.20 (d) (e) 3 59.7 cm 1.51� 10 kg/cm 2 �1 3 59.4 (a) (i) 672 h � 2 � r (ii) Refer to solution (b) dA �1344 � 1 � �r �� � 336� 2 dr � � �r (c) r � 6.24 (d) (e) Chapter 16 Exercise 60 60.1 2 184 cm 8 buckets f x x x x 3 2 ( ) � 2 � �8 � 7 60.2 (a) 1 3 3 f ( x) � x �36x � � 98 3 x (b) a � 1.5 f( x) 60.3 (a) 1 3 2 � x � 32x �12x �1008 3 (b) 1008 (c) 3024 60.4 (a) 100 20 f( x) 1 2 x x (b) b � 20 Exercise 61 61.1 (a) (i) 10 (ii) (7.67, 50.8) (b) (i) 3 2 10��x �16x � � � �dx 3 ��69x �90 � (ii) 2401 12 61.2 (a) (i) � 5 (ii) (5, 0) (b) (i) (ii) � 0 �5 3 2 �x � 5x � � �dx ��25x �125� 6875 12 www.seprodstore.com 371