Finding Derivatives - HP 39g+ User Manual

Symbolic
calculations in the
Function aplet

Finding derivatives

To find derivatives
in HOME
Using mathematical functions
You can perform symbolic operations in the Function
aplet's Symbolic view. For example, to find the derivative
of a function in the Function aplet's Symbolic view, you
define two functions and define the second function as a
derivative of the first function. You then evaluate the
second function. See "To find derivatives in the Function
aplet's Symbolic view" on page 11-22 for an example.
The hp 39g+ can perform symbolic differentiation on
some functions. There are two ways of using the hp 39g+
to find derivatives.
•
You can perform differentiations in HOME by using
the formal variables, S1 to S5.
•
You can perform differentiations of functions of X in
the Function aplet.
To find the derivative of the function in HOME, use a
formal variable in place of X. If you use X, the
differentiation function substitutes the value that X holds,
and returns a numeric result.
For example, consider the function:
2
( x ( )
dx sin + 2 cos
1. Enter the differentiation function onto the command
line, substituting S1 in place of X.
2
2. Evaluate the function.
x ( ) )
S1
S1
S1
11-21