Analysis and Approaches for IBDP Maths Ebook 2 | Page 265

(e) (1)
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n
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n � � �
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� 4n � 4 � ln( n �1) � 4n � ln n � 4 �
n
1
An
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n
1 n
An
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n n�1
1 n �1
(2) An
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� �ln
n�1 n�2
1 n 1 n�1
(3) An
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1
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n n �1 n �1 n � 2
n �1�
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An
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n
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n( n �1) n �2
(f)
13 13 e
A �
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1 � 13 13
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1
1 �
13
13
� ln � ln e � ln
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1 � 1 13
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1 1
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20
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