Differential Calculations - Casio FX-9750G Quick Start Manual

3-3 Differential Calculations

P.64
The differentiation for this type of calculation is defined as:
In this definition, infinitesimal is replaced by a sufficiently small $
the neighborhood of f ' (a) calculated as:
In order to provide the best precision possible, this unit employs central difference to
perform differential calculations. The following illustrates central difference.
The slopes of point
y = f(x)
In the above, $
difference.To calculate derivatives, the unit takes the average between the value of
$
• To perform differential calculations, first display the function analysis menu, and
then input the values shown in the formula below.
d dx f(x)
2( /
)
d/dx ( f (x), a, $x) & ––– f (a)
f (a + $x) – f (a)
f '(a) = lim –––––––––– –––
$x'0
f (a + $x) – f (a)
f '(a) –––––––––– –––
a
are as follows:
f (a + $x) – f (a)
–––––––––– ––– = ––– , –––––––––– ––– = –––
$x
y x
/$ is called the forward difference, while %
y x y x
/$ and % /% , thereby providing higher precision for derivatives.
a x
, ,$ )
Increase/decrease of
Point for which you want to determine the derivative
d
dx
$x
$x
a + x
and point , and of point
$
y
f (a) – f (a – $x)
$
$x $x
x
x
, with the value in
a a – x
and point in function
$
y
%
%x
y x
/% is the backward
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