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 | and |
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| keys transforms the |
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graph, with these |
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transformations reflected in the equation. |
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The button labelled | is |
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| Origin |
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a toggle between |
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and | . When |
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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 | and |
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keys control vertical and |
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horizontal transformations. When | is chosen the |
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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 amplitude and frequency of the graph. This is most easily seen by experimenting.
Pressing 
displays the equation at the top of the screen. The equation is controlled by the graph. Pressing the 
and 
keys moves from parameter to parameter. Pressing the 
parameter’s values.
Extremum
or 
key changes the
The default angle setting for this aplet is radians. The angle setting can be changed to degrees by pressing 
.
Getting started |