Apps. and Interpretation for IBDP Maths Ebook 1 | Page 78

Your Practice Set – Applications and Interpretation for IBDP Mathematics
(c) v
13
(d)
(e) uk � vk
�v
� (M1) for valid approach
1
13 1
r �
40 13�1
� � 3
729
� 29160
A1 N2
The sum of the first 13 terms
13
v (1 )
1
� r
�
(M1) for valid approach
1�
r
40 (1 3 13
� )
� 729
(A1) for substitution
1�
3
� 43739.97257
� 43740
A1 N2
264 ( 1)(12)
40
729
3
40 k�1
264 �12k
�12 � � 3
729
40 k�1
252 �12k
� �3 � 0
729
(A1) for correct equation
By considering the graph of
40 k�1
y� 252 �12k� � 3 , k � 9 .
729
A1 N2
k�1
� k � � � (M1) for setting equation
[2]
[3]
[3]
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