MathGroup Archive 2007

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Expansion symbolic

  • To: mathgroup at smc.vnet.net
  • Subject: [mg74797] Re: Expansion symbolic
  • From: dh <dh at metrohm.ch>
  • Date: Thu, 5 Apr 2007 04:15:56 -0400 (EDT)
  • Organization: hispeed.ch
  • References: <euvm0k$cc5$1@smc.vnet.net>


Hi Dominic,

try: ...//TraditionalForm

Note, that output from TraditionalForm can not necessarily given as 

input to Mathematica.

Daniel



Dominic Jackson wrote:

> Could anyone please tell me how to instruct Mathematica to expand the

> expression below with respect to the powers of x.  I would like the

> constants c1,c2,c3 and c4 to stay behind the summation sign but the powers

> of x to cross over to multiply x^(k+i).

> 

> 

> 

> (c1 (x^2) +c2 (x^3))* D[(Summation sign i=0 to infinity) Subscript[a,i+1][k]

> * x^(k+i),{x,2}]//Expand.

> 

> 

> 

> This is what I get

> 

> 

> 

> c1 x^2 *(Summation sign i=0 to infinity) (k+i)*(k+i-1) *Subscript[a,i+1][k]

> * x^(k+i-2)

> 

> 

> 

> + c2 x^3 *(Summation sign i=0 to infinity) (k+i)*(k+i-1)

> *Subscript[a,i+1][k] * x^(k+i-2)

> 

> 

> 

> And this is what I want to achieve.

> 

> 

> 

> c1 *(Summation sign i=0 to infinity) (k+i)*(k+i-1) *Subscript[a,i+1][k] *

> x^(k+i)

> 

> 

> + c2 *(Summation sign i=0 to infinity) (k+i)*(k+i-1) *Subscript[a,i+1][k] *

> x^(k+i+1)

> 

> Any clues.

> Thanx.

> 

> Dom

> 




  • Prev by Date: Re: Integral of Piecewise function involving DiracDelta
  • Next by Date: Re: how to get the area of circles
  • Previous by thread: Re: Expansion symbolic
  • Next by thread: bug in Integrate