In Maxima, it is generally best to work with *symbolic expressions*
rather than *defined functions*.
Thus your example would become
f : (1-%e^(2*x))/(1+%e^(2*x));
df : diff(f(x),x);
at(df,x=1);
or
ev(df,x=1);
or
subst(x,1,df)
or
subst(x=1,df)
If you want to define a function to calculate with, you can also define it:
define( myfun(x), df )
There is also a shortcut syntax for this:
myfun(x) := ''(df)$
(note: that is two single-quotes in a row, not a double-quote)
-s
On Mon, Sep 14, 2009 at 4:52 AM, Hans W. Hofmann <hawe at chefmail.de> wrote:
> f(x):=(1-%e^(2*x))/(1+%e^(2*x));
> df(x):=diff(f(x),x)$
> df(1);
> (%o11) Non-variable 2nd argument to diff:1
> #0: df(x=1) -- an error. ?To debug this try debugmode(true);
>
> I'm not able to calculate diff'd and intergrate'd functions
> how to do?
>
> Gru? HW
>
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