Casio fx-180P - Integrals; Defining Functions for Integration; Executing Integral Calculations

8/INTEGRALS
“To
carry
out
integrals,
(i)
define
(write)
function
ffx}
during
the
“LRN”
mode,
then
(2
designate
the
interval
of
integral
during
the
’’fdx’’
mode.
f(b) y= ffx)
We calculate area Sfexyax.
x
——
N equa! parts
*The
approximation
method
used
for
integrating
the
function
written
in
Pl
or
P2
is
the
Simpson's
rule.
This
method
requires
to
Givide
the
interval
of
integral
into
equal
parts.
If
the
number
of
divisions
is
not
specified,
the
calculator
determines
it
by
itself
according
to
the
form
of
the
function.
To
specify
it,
designate
n
{an
integer
of
t
to
9}
which
meets
N
=
2?
where
N
is
the
number
of
divisions.
® Defining function f/x)
1)
Select
the
“LRN”
mode
(press
d
2)
Designate
a
program
number
{press
()
or
4
F}.
3) Press @ &) .
*
This
is
needed,
as
the
first
program
step,
to
assign
variable
x
of
the
function
Sfx)
to the M-register,
4)
Write
the
expression
of
function
Sfx)
by
true
atgebraic
logic.
Use
fa
to
represent
variable
x.
Write
Ei
at
the
end,
i .
Example:
For
f/x)
“Pa
7
Write
the
sequence
of
1,
=,
((.
MR,
INV
x?_4,1,}],
=.
5)
Press
(a)
@)
to
select
the
“fdx"
mode.
Note:
For
a
function
ffx)
whose
variable
x
cannot
take
the
zero
value,
input
an
appro-
priate
number
in
between
steps
1)
and
2)
above.
Do
not
use
constant
registers,
.
@)
and
during
expressing
a
function
{step
4).
= Execution of integral
1)
Select
the
‘‘fdx"
mode
(press
@aQ(7)
),
2)
Designate
the
program
number
assigned
to
the
function,
f/x).
(Press
©
or
@
&.)
3)
Press
a
sequence
of
7
(im)
to
specify
division
number
N
(this
will
be
displayed),
This
step
may
be
skipped,
4)
Designate
the
interval
of
integral,
[¢,
5}.
(Press
a
A
ba.)
*
In
seconds
or
minutes
the
result
will
be
displayed
in
a
floating
point
representa-
tion.
~37—
x
A
.
Pps
ke
read
eo
ta
Ate
a
KG
Mahe
Ate
lat
anlar
a
Att this time the memory registers contain the following data.
K\1-register (Press Ke} } 2... 1a
Ki2-register {Press Kal @} .. 1b
spans {Press (eel) (3) } -N (= 27}
4-register (Press {ke @) ) Sta) ‘
K(5-register (Press EB} ..., fe)
6-register (Press Ga @ ) J S(xjdx
eee {Press MY)... 2. a
#/Example
$ 8
| For fix} = 2x? + 3x 4 4, calculate Sy ffx}dx and f ftxjax.
OPERATION READ-OUT
(Designate program No.}
Writing f(x)
© bd
(Write S()} 283663030648
(Gelect “fdx" mode) tae (1)
(Designate program No.) FY O, ane, :
Ulpput 7) 2he ” 4. ume |N displayed S Stexjax
Result displayed in
2658 about 4 seconds
(Designate program No.)
264 Bk
{IInput @ and b) 1.215000000 9?
8
Result displayed in Sf Sfxsdx
about 6 seconds
(Gpput a and b) 4.500000000_ °2
| sol 2}
|
com
{—*.
>
| a) a ae
caw [ye |e
| ms | “ise |
|
ee
[
“eso.
[iPr