Analysis and Approaches SL Practice Paper Book | Page 19

� � � b , where the ( r �1 ) r�0 r

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Binomial Theorem
� Properties of the n factorial n !: 1 . n! � n�( n �1 ) �( n � 2 ) � �3�2�
1
2 . 0 ! � 1 3 . n! � n�( n � 1 )!
� Properties of the combination coefficient
�n� n!
1 . � � �r � r!( n � r)!
2 .
� n�
� n�
� �
�� �
�1
� 0�
� n�
3 .
� n�
� n
� �
��
�n �1�
� n
�1�
4 .
n n n( n
1 )
� r �
� n
� r
( n r
1 ) r!
�n� � �: �r
� The binomial theorem : �n� � n� � n� � n � � n�
( a � b)
� � �a b � � �a b � � �a b � � � �a b � � �a b �0� �1� � 2� � n�1� � n�
� n n 0 n�1 1 n�2 2 1 n�1 0 n
�n� a � �
n n�r r
� � � b , where the ( r �1 ) r�0 r
�n� -th term � �a �r
� n�r b r

8

Proofs and Identities
� Identity of x : The equivalence of two expressions for all values of x
� : Identity sign www . seprodstore . com
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