TI-92 -- Vector-Valued Functions
You can define a vector-valued function on the TI-92 in the obvious way
as shown by the screen below.
The TI-92 parametric graphing mode can produce nice graphs for
vector-valued functions whose values are in R^2. Consider, for example,
the function
P(t) = (30 t, 5 + 20 t - 16 t^2)
that describes the travels of a baseball thrown with an initial velocity
of 30 feet per second horizontally and 30 feet per second vertically from
a height of 5 feet. The following screen defines this function.
To look at this function in parametric graphing mode press the MODE
key and then select the graph mode PARAMETRIC as shown in the
screen below. Don't forget to pree ENTER twice.
Next go to the Y= screen and define xt1 and yt1
as shown in the screen below.
Notice the syntax. xt1 is the first coordinate of the vector-valued
function and is denoted by
p(t)[1, 1]
and yt1 is the second
coordinate of the vector-valued function and is denoted by
p1(t)[1, 2].
Next set up the window screen as shown below
There are three ranges that must be set -- the range for the time variable
t, the range for the x-coordinate variable x, and the range
for the y-coordinate variable y. The screen below shows the graph
produced by the window settings above.
Notice that with these settings the baseball doesn't quite hit the ground because
the range for the time variable t is not quite long enough.
Copyright c 1995 by
Frank Wattenberg, Department of Mathematics, Carroll College,
Helena, MT 59625