Function calculations, E-20, Dx d – Casio fx-115ES PLUS User Manual
Page 21
E-20
Function Calculations
For actual operations using each function, see the “Examples” section
following the list below.
ππ : π is displayed as 3.141592654, but π = 3.14159265358980 is used for
internal calculations.
e
:
e
is displayed as 2.718281828, but
e
= 2.71828182845904 is used for
internal calculations.
sin, cos, tan, sin
−1
, cos
−1
, tan
−1
: Trigonometric functions. Specify the
angle unit before performing calculations. See
1
.
sinh, cosh, tanh, sinh
−1
, cosh
−1
, tanh
−1
: Hyperbolic functions. Input a
function from the menu that appears when you press
w. The angle unit
setting does not affect calculations. See
2
.
°,
r
,
g
: These functions specify the angle unit. ° specifies degrees,
r
radians,
and
g
grads. Input a function from the menu that appears when you perform
the following key operation:
1G(DRG'). See
3
.
$
,
%
: Exponential functions. Note that the input method is different
depending upon whether you are using Natural Display or Linear Display.
See
4
.
log
: Logarithmic function. Use the
l key to input log
a
b as log (
a
,
b
). Base
10 is the default setting if you do not input anything for
a
. The
& key also
can be used for input, but only while Natural Display is selected. In this
case, you must input a value for the base. See
5
.
ln
: Natural logarithm to base
e
. See
6
.
x
2
,
x
3
,
x
^, ), #, ",
x
−1
: Powers, power roots, and reciprocals. Note
that the input methods for
x
^, ), #, and " are different depending upon
whether you are using Natural Display or Linear Display. See
7
.
Note: • The following functions cannot be input in consecutive sequence:
x
2
,
x
3
,
x
^,
x
−1
. If you input 2
ww, for example, the final w will be ignored.
To input 2
2
2
, input 2
w, press the d key, and then press w(B).
•
x
2
,
x
3
,
x
−1
can be used in complex number calculations.
: Function for performing numerical integration using the Gauss-Kronrod
method. Natural Display input syntax is
∫
a
b
f
(
x
), while Linear Display input
syntax is
∫
(
f
(
x
),
a
,
b
,
tol
).
tol
specifies tolerance, which becomes 1
×
10
–5
when nothing is input for
tol
. Also see “Integration and Differential
Calculation Precautions” and “Tips for Successful Integration Calculations”
for more information. See
8
.
F
: Function for approximation of the derivative based on the central
difference method. Natural Display input syntax is
dx
d
(
f
(
x
))
x
=
a
, while
Linear Display input syntax is
dx
d
(
f
(
x
),
a
,
tol
).
tol
specifies tolerance,
which becomes 1
× 10
–10
when nothing is input for
tol
. Also see “Integration
and Differential Calculation Precautions” for more information. See
9
.
8
: Function that, for a specified range of
f
(
x
), determines sum
Σ
(
f
(
x
))
x=a
b
=
f
(
a
) +
f
(
a
+1) +
f
(
a
+2) + ...+
f
(
b
). Natural Display input syntax is
Σ
(
f
(
x
))
x=a
b
,
while Linear Display input syntax is
Σ(
f
(
x
),
a
,
b
).
a
and
b
are integers that