Texas Instruments 83PL/CLM/1L1/V - 83 Plus Calc, Руководство пользователя

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TI-83 Plus Math, Angle, and Test Operations 70
nDeriv(
nDeriv(
(numerical derivative) returns an approximate derivative of
expression
with respect to
variable
, given the
value
at which to calculate the
derivative and
H
(if not specified, the default is 1
â
L
3).
nDeriv(
is valid only
for real numbers.
nDeriv( expression , variable , value
[
,
H
]
)
nDeriv(
uses the symmetric difference quotient method, which
approximates the numerical derivative value as the slope of the secant
line through these points.
ε
ε ε
2
) ( ( ) (
) ( '
− − +
=
x f x f
x f
As
H
becomes smaller, the approximation usually becomes more
accurate.
You can use
nDeriv(
once in
expression
. Because of the method used to
calculate
nDeriv(
, the TI-83 Plus can return a false derivative value at a
nondifferentiable point.