Slopefields on the TI86
Given a differential equation, say y' = 3xy, here is how
to make the TI86 draw a slopefield for that differential equation.

Put the calculator into Differential Equation mode: Press [2nd]
[MODE] and select DifEq as shown:

We must translate the differential equation: In place of the function (y
in
this case), write Q1, and in place of the variable (x in
this case), write t. So we get
Q1' = 3tQ1, or as the calculator wants it, Q'1=3tQ1.

Now press [GRAPH][Q'(t)=] and enter our differential equation
from the last step on the first line:

Press [EXIT][MORE][FORMT] and make sure that, at the bottom
of the screen, both SlpFld is selected:

Finally, press [WIND] to select a suitable window: (Set
x
and y ranges as usual; you can ignore t for now), and
then press
[GRAPH].
Last Modified December 7, 1998.
Prof.
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