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Paper 2 – Miscellaneous Problems
Example
The function f is defined by
2 f ( x) ax bx c
� � � , where a , b , c� . It is given that the graph of f passes through ( � 10 , 540 ) , ( 10 , 500 ) and ( 20,1980 ) .
( a ) ( i ) Show that 100a �10b � c � 540 .
( ii ) Write down the other two equations in a , b and c .
The above three equations can be expressed in a matrix equation
3� 3 matrix , and
�a �
� � X � b and B are two 3� 1 matrices .
�c �
� �
AX �
[ 3 ]
B , where A is a
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( b ) Write down
( i ) A ;
( ii ) B ;
( iii )
�1
A .
( c ) Hence , find the values of a , b and c .
( d ) Find
[ 4 ]
[ 2 ]
( i ) the equation of the axis of symmetry ;
( ii ) the y -coordinate of the vertex . [ 4 ] www . seprodstore . com
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