HP 40gs, Руководство пользователя, Страница: 292 / 444

16-18 Step-by-Step Examples
Part 4
To calculate , begin
by typing: DERVX(Y(t)) .
Pressing returns:
Press again to
simplify the result:
Select FACTOR and press
.
You can now define the
function
(in the same
way that you defined
).
Part 5
To show the variations of and , we will trace
and on the same graph.
The independent variable must be
t
which it should be as
a result of the previous calculations. (You can check this
by pressing
.)
Type X(t) in the Equation
Writer and press .
The corresponding
expression is displayed.
Now press , select
Function , press ,
select F1 as the destination and press .
Now do the same thing with Y(t), making F2 the
destination.
To graph the functions, quit
CAS
(by pressing ),
choose the Function
aplet, and check F1 and
F2 .
y
′
t
( )
y
′
t
( )
x
′
t
( )
x t
( )
y t
( )
x t
( )
y t
( )
hp40g+.book Page 18 Friday, December 9, 2005 1:03 AM