Re: Wrong partial derivatives calculated
- To: mathgroup at smc.vnet.net
- Subject: [mg41148] Re: Wrong partial derivatives calculated
- From: "Martin Manscher" <please.respond at in.newsgroup>
- Date: Tue, 6 May 2003 05:54:32 -0400 (EDT)
- References: <b9514r$r86$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
David, You need a space between x and y. "xy" is interpreted as a variable called xy, "x y" is interpreted as x times y. Martin "David" <david at hushmail.com> wrote in message news:b9514r$r86$1 at smc.vnet.net... > When I calculate (D[x^2 + xy + y^2, x) mathematica gives me 2y and when I > calculate D[x^2 + xy + y^2, y) I get 2x. These are wrong answers -- have I > got the syntax right? I'm trying to find partial derivatives of x^2 + xy + > y^2 with respect to x and y. > > Thanks, > > David > > >