A 
button is provided to evaluate the student’s knowledge. Pressing 
displays a target quadratic graph. The student must
manipulate the equation’s parameters to make the equation match the target graph. When a student feels that they have correctly chosen the parameters a 
button evaluates the answer and provide feedback. An
button is provided for those who give up!
Trig Explorer aplet The Trig Explorer aplet is used to investigate the behaviour of the graph of y = a sin(bx + c) + d as the values of a, b, c and d change, both by manipulating the equation and seeing the change in the graph, or by manipulating the graph and seeing the change in the equation.
Press 
, select Trig Explorer, and then press 
to display the screen shown right.
In this mode, the graph |
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controls the equation. |
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Pressing the |
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graph, with these |
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transformations reflected in the equation. |
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The button labelled |
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a toggle between |
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and |
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is chosen, the ‘point of |
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control’ is at the origin (0,0) |
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and the |
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keys control vertical and |
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horizontal transformations. When |
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‘point of control’ is on the first extremum of the graph (i.e. for the sine graph at (π ⁄ 2,1) .
The arrow keys change the | Extremum |
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amplitude and frequency of |
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the graph. This is most easily |
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seen by experimenting. |
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Getting started |