Differential Calculations - Casio FX-7400G User Manual

• To perform differential calculations, first display the Option Menu, and then input
the values shown in the formula below.
K2(CALC)[
d dx f(x)
1( /
)
d/dx ( f (x), a, !x) $ ––– f (a)
The differentiation for this type of calculation is defined as:
f (a + !x) – f (a)
f '(a) = lim –––––––––– –––
!x#0
In this definition, infinitesimal is replaced by a sufficiently small !
the neighborhood of f ' (a) calculated as:
f (a + !x) – f (a)
–––––––––– –––
f '(a)
In order to provide the best precision possible, this unit employs central difference to
perform differential calculations. The following illustrates central difference.
a
The slopes of point
y = f(x)
are as follows:
f (a + !x) – f (a)
–––––––––– ––– = ––– , –––––––––– ––– = –––
!x
y x
In the above, ! /! is called the forward difference, while "
difference.To calculate derivatives, the unit takes the average between the value of
y x y x
/! and " /" , thereby providing higher precision for derivatives.
!

Differential Calculations

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
Chapter 3
x
x
, with the value in
a a – x
and point in function
!
y
"
"x
y x
/" is the backward
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