Using Sliders on the
TI-Nspire CAS handheld.
Quadratic functions
This document assumes you have a basic knowledge of how the TI-Nspire CAS handheld operates.
Task: investigate the effect of “a” on the
function f1(x) = a*x2
1. Open Graphs &Geometry application.
2. Press b/1:Actions/A: Insert Slider
3. When the slider is surrounded by a solid border you
can use /+b and choose Slider Settings to edit as
shown. Note: you can also edit the settings by
clicking on the parameters in the slider.
Note: you can enter the function first and then the
slider. In that case no graph would appear until the
slider variable is defined.
© Texas Instruments Australia 2008 Author: Russell Brown
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4.
In the function entry line type in the function:
f1(x) = a*x2 . If the entry line is not visible press
/+G. After entering the function press /+G to
hide the entry line.
Note: you must use a multiplication sign between the
a and the x.
Grab the slider control and change the value of a.
Observe the graph shape.
Note: to grab the whole slider box to relocate it make
sure you have a dotted box around the slider before
grabbing. After grabbing it may go to a solid line but
that is OK.
5. The slider shown opposite has been minimized. This
means that you use the arrow keys to move the slider
rather than dragging the pointer. To minimize, select
the slider and use /+b, choose Minimize.
Note: Setting Min & Max values in Slider Settings
sets the display and limits the slider control by
dragging. When in minimize mode there is no limit in
either direction and will go in the step size chosen in
the Slider Settings box (default is 1)
6. When in minimize mode move cursor onto the up (or
down) arrow as shown opposite – it will then
highlight. Press click button repeatedly to change the
values.
7. Double click on the function label on the screen and
edit as shown opposite. Press · to accept the
change.
Note: notice that the graph disappears. Add another
slider and allocate to the variable b. You could have
added this slider before editing the original function so
the graph always remained on the screen.
© Texas Instruments Australia 2008 Author: Russell Brown
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If you wish you can add another slider to show the
effect of changing “c” in:
f1(x) = a*x2 + b*x + c
© Texas Instruments Australia 2008 Author: Russell Brown
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