2 . The vectors a and b are given as
�1�
� � a � 2 and
�3�
� �
� 1 � � � b � �1 .
��5�
� �
( a ) Write down 3a�
2b .
( b ) Hence , find the component of 3a�
2b perpendicular to a .
[ 1 ]
[ 3 ]
3 . The coordinates of two points A and B are A ( 2 , 6 , 3 ) and B ( 3 , 4 , � 2 ) . Let O be the origin .
( a ) Find the component of OA � parallel to OB � . [ 3 ]
( b ) ( i ) Find OA � .
( ii ) Hence , find ˆ AOB .
4 . The coordinates of two points A and B are A ( 3,12 , 4 ) and B ( 5 , 3,1 ) . Let O be the origin .
[ 4 ]
8
( a ) Find the component of OA � perpendicular to OB � .
( b ) ( i ) Find OA � .
[ 3 ]
( ii ) Hence , find ˆ OAB . [ 4 ] www . seprodstore . com
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