Apps. and Interpretation for IBDP Maths Ebook 2 | Page 66

Your Practice Set – Applications and Interpretation for IBDP Mathematics

19

Paper 1 – Real and Imaginary Parts
Example
( a ) Express
( b ) Express
1 z � in the form a� bi , where a , b� .
2 i
3
z in the form a� bi , where a , b� .
( c ) Hence , write down the imaginary part of
3
z .
[ 2 ]
[ 2 ]
[ 1 ]
Solution
( a )
1 2 1 � � i
2 � i 5 5
A2
[ 2 ]
( b )
3 �2 1 � z ��
i � �5 5 �
3
( c )
3 2 11 z � � i
A2
125 125
11
� A1 125
[ 2 ]
[ 1 ]
Exercise 19
1 . ( a ) Express
( b ) Express
1 z � in the form a� bi , where a , b� .
3 4i
2
z in the form
( c ) Hence , write down the real part of
a� bi , where a , b� .
2
z .
[ 2 ]
[ 2 ]
[ 1 ]
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