Re: Symbolic calculation problem
- To: mathgroup at smc.vnet.net
- Subject: [mg37789] Re: [mg37774] Symbolic calculation problem
- From: Andrzej Kozlowski <andrzej at tuins.ac.jp>
- Date: Wed, 13 Nov 2002 01:10:57 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
I am not sure if I understand you correctly. However, in the first case
all you seem to need is to apply Simplify to the final answer, i.e.
Simplify[Inverse[{{c, d}, {e, c}}.{{c, e}, {i, c}}].{c, e}]
As for the second part: do you want to express H in terms of c,d,x1,x2
and x3 ???
You can do it with:
In[13]:=
Solve[{{a, b} == {c, d}, {w1, w2} == {x1*c + x2*d,
x3*c + x4*d}, H == w1*a + w2*b}, H, {a, b, w1, w2}]
Out[13]=
{{H -> c^2*x1 + c*d*x2 + c*d*x3 + d^2*x4}}
Andrzej Kozlowski
Yokohama, Japan
http://www.mimuw.edu.pl/~akoz/
http://platon.c.u-tokyo.ac.jp/andrzej/
On Tuesday, November 12, 2002, at 05:13 PM, Pasi Ylijukuri wrote:
> I have problem to calculate exact answer.
>
> Input:
>
> {a, b} == Inverse[{{c, d}, {e, c}}.{{c, e}, {i, c}}].{c, e}
>
> And output (I cant paste it here):
>
> http://www.ee.oulu.fi/~poy/Math.jpg
>
>
> So you can see the problem (It doesnt subtract all like:
> -r/(s+w)+(r+t)/(s+w) have to be t/(s+w)).
>
>
>
> Second proble:
>
> How i do that in Mathematica 4.2:
>
> {a,b}=={c,d}
> {w1,w2}={x1*c+x2*d,x3*c+x4*d}
>
> and then solve (place beore symblic calculations)
>
> H=w1*a+w2*b
>
>
> ??
>
>
>
>
