substituting function in diff
- Subject: substituting function in diff
- From: Robert Dodier
- Date: Tue, 14 Jul 2009 12:09:01 -0600
On Tue, Jul 14, 2009 at 5:51 AM, David Webb<david.webb at noc.soton.ac.uk> wrote:
> (%i1) inflag : true;
> (%o1) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?true
> (%i2) G : diff(f(x,z),z,1);
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? d
> (%o2) ? ? ? ? ? ? ? ? ? ? ? ? ? ?-- (f(x, z))
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? dz
> (%i3) H : cons(p(x)*q(z),rest(G));
> Attempt to differentiate with respect to a number:
> 1
How about this:
G : diff(f(x, z), z, 1);
subst (f(x, z) = p(x) * q(z), G);
=> 'diff(p(x)*q(z),z,1)
Were you hoping to see something else?
Robert Dodier