Your Practice Set – Applications and Interpretation for IBDP Mathematics
13
Paper 1 – Trigonometric Identities
Example
Let cos� � 0.28 , where � is acute . Using trigonometric identities to find
( a ) sin� ;
( b ) tan� .
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Solution
( a )
( b )
2 sin�
� 1�
cos �
2 sin� � 1� 0.28 ( A1 ) for substitution sin� � 0.96 A1
|
sin� tan�
� cos�
|
|
0.96 tan� �
0.28
|
( A1 ) for substitution |
|
24 tan� �
7
|
A1 |
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[ 2 ]
Exercise 13
1 . Let
5 sin� � , where � is obtuse . Using trigonometric identities to find
13
( a ) cos� ;
( b ) tan� .
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[ 2 ]
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