RE: How do u go about doing this---?
- To: mathgroup@smc.vnet.net
- Subject: [mg10921] RE: [mg10844] How do u go about doing this---?
- From: "Barthelet, Luc" <lucb@ea.com>
- Date: Thu, 12 Feb 1998 20:16:02 -0500
F[x_,y_]:=(Sin[x]+Cos[y])/(Sin[x]-Cos[y]); Simplify[ D[F[x,y],x]^2+D[F[x,y],y]^2 ] returns the appropriate result. >-----Original Message----- >From: McAllister [SMTP:lmcallister@email.msn.com] To: mathgroup@smc.vnet.net >Sent: Tuesday, February 10, 1998 6:02 PM >To: mathgroup@smc.vnet.net >Subject: [mg10844] How do u go about doing this---? > > >Let f(x) = sin(x)+cos(y) > ----------------- > sin(x) - cos(y) > >Show that > (df/dx)^2 + (df/dy)^2 = > > 2+cos(2(x-y))+cos(2(x+y)) > ----------------------------------- > (sin(x)-cos(y))^4 > > >Thanks, > >L. > > >