Re: Peculiar output from DSolve
- To: mathgroup at smc.vnet.net
- Subject: [mg36998] Re: [mg36994] Peculiar output from DSolve
- From: BobHanlon at aol.com
- Date: Sun, 6 Oct 2002 05:32:33 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
In a message dated 10/4/2002 5:13:02 AM, selwynh at earthlink.net writes:
>In: DSolve[y*D[u[x, y],x] == x*D[u[x, y],y], u[x,y], {x, y}]
>
>Out: {{u[x, y] -> C[1][(1/2)*(x^2 + y^2)]}}
>
>Square brackets are used as grouping symbols in the result!?? :^O
>
>Somebody say it isn't so.
>
"It isn't so"
The square bracket is not delineating a factor it is enclosing the argument
to an arbitrary function named C[1]. While the function is dependent on both
x and y the dependence only occurs in the combination (x^2+y^2).
Bob Hanlon