Re: implicit differentiation
- Subject: [mg2883] Re: [mg2858] implicit differentiation
- From: me at talmanl.mscd.edu (Lou Talman)
- Date: 4 Jan 1996 03:54:30 -0600
- Approved: usenet@wri.com
- Distribution: local
- Newsgroups: wri.mathgroup
- Organization: Wolfram Research, Inc.
- Sender: mj at wri.com
An alternative to Dave Wagner's use of Dt to implement
implicit differentiation is to make the dependence explicit:
In[1]:=
imp[u_, v_] := Log[v] + u v - 1
In[2]:=
Map[D[#, x]&, imp[x, y[x]] == 0]
Out[2]=
y'[x]
y[x] + x y'[x] + ----- == 0
y[x]
In[3]:=
Solve[%, y'[x]]
Out[3]=
2
y[x]
{{y'[x] -> -(----------)}}
1 + x y[x]
--Lou Talman
-------------------------------
Begin forwarded message:
>From: marshall at CIS.Edu.HK
>Subject: [mg2858] implicit differentiation
How can I do implicit differentiation ?