Re: A question of simplification
- To: mathgroup at smc.vnet.net
- Subject: [mg21023] Re: [mg20953] A question of simplification
- From: BobHanlon at aol.com
- Date: Thu, 2 Dec 1999 21:41:34 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
If you mean to multiply c and f[x] rather than take their dot product then it works as you intend D[c*f[x], x] c*Derivative[1][f][x] Otherwise, tell it that a dot product with zero is zero D[c . f[x], x] /. 0 . x_ :> 0 c . Derivative[1][f][x] Bob Hanlon In a message dated 12/1/1999 3:25:49 AM, eexiong at ee.ust.hk writes: >In Mathematica, when using partial differentiation, we get >D[c.f[x]]=0.f[x]+c.f'[x], not c.f'[x]. So, when the equation is long, >the result will be very tedious. >How can I simply the result to c.f'[x]? I have tested Simplify and >FullSimplify. It does not work. >