Apps. and Interpretation for IBDP Maths Ebook 1 | Page 144

Your Practice Set – Applications and Interpretation for IBDP Mathematics
38
Paper 1 – Sketching Trigonometric Functions
Example
Let f ( x) � 4cos(90 x)
, for 0�x
� 4.
(a) (i) Write down the amplitude of f .
(ii) Find the period of f .
(b) On the following grid sketch the graph of f .
[3]
[4]
Solution
(a) (i) The amplitude of f is 4. A1 N1
(ii)
The period of f
�360 � 90
(M1) for valid approach
� 4
A1 N2
[3]
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