HP 40gs User Manual
Page 292
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