HP 40gs User Manual page 291

hp40g+.book Page 17 Friday, December 9, 2005 1:03 AM
Part 3
Step-by-Step Examples
Then press to
produce the result at the
right:
In other words,
( ) y t ( )
y t – = –
.
x t ( ) y t ( )
M ( , )
If is part of
1
Γ
part of .
M M
Since and are symmetrical with respect to the x-
1 2
axis, we can deduce that the x-axis is an axis of symmetry
Γ
for .
x' t ( )
Calculate by typing:
DERVX
X
t. Press
to highlight the
expression.
Pressing returns the
result at the right:
Press to simplify the
result:
Y
ou can now define the
x' t ( )
function by invoking
DEF.
Note: You will first need to type =X1(t) then exchange
X1(t) with the previous expression.
To do this, highlight X1(t)
and type .
Now select the entire
expression and apply the
DEF command to it:
Finally press to
finish the definition.
Γ ( ) y t – ( )
M ( x t – , )
, then
x
is also
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