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RE: Odd results in integration

• To: mathgroup at smc.vnet.net
• Subject: [mg32883] RE: [mg32871] Odd results in integration
• From: "David Park" <djmp at earthlink.net>
• Date: Mon, 18 Feb 2002 05:22:02 -0500 (EST)
• Sender: owner-wri-mathgroup at wolfram.com

Tomas,

It only looks different. That is because of the natural sorting order. For
example b comes before y but y comes before beta. If you convert the outputs
to TraditionalForm they will look more nearly alike, but still have the
factors in a different order.

David Park
djmp at earthlink.net
http://home.earthlink.net/~djmp/

> From: Tomas Garza [mailto:tgarza01 at prodigy.net.mx]
To: mathgroup at smc.vnet.net
>
> This problem has been brought to my attention, and I am puzzled as to
> what's going on. The following indefinite integral is readily evaluated
> by Mathematica:
>
> In[1]:=
> Integrate[(a - y)^(2*n - 1)/(b - y)^n, y]
> Out[1]=
> ((a - y)^(2*n)*(-b + y)*Hypergeometric2F1[1 - n, 1 - 2*n,
>     2 - n, -((b - y)/(a - b))])/(((-a + b)*(-1 + n))*
>    ((1 + (b - y)/(a - b))^(2*n)*(b - y)^n))
>
> where a, b and n are constants. However, if in the above input cell one
> uses the greek letters "alfa" and "beta" (through Esc a Esc and Esc b
> Esc) instead of a and b, respectively, the result turns out to be
> different.
>
> Tomas Garza
> Mexico City
>
>