       FullSimplify issue

• To: mathgroup at smc.vnet.net
• Subject: [mg124150] FullSimplify issue
• From: Tiago <aswedieinparadise at gmail.com>
• Date: Wed, 11 Jan 2012 04:21:52 -0500 (EST)
• Delivered-to: l-mathgroup@mail-archive0.wolfram.com

```Hello,

I want to simplify an expression. FullSimplify does it only if I
include an assumption that has nothing to do with the expression that
I want to simplify. Here is the code:

ListOfAssumptions = {
b c - b c == 2 Area,
p + q + 1 == 0,
p + q + 1 == 0,
p + q + 1 == 0,
b + b + b == 0,
c + c + c == 0,
(b b + c c)/s^2 == p,
(b b + c c)/s^2 == p,
(b b + c c)/s^2 == p,
(b b + c c)/s^2 == q,
(b b + c c)/s^2 == q,
(b b + c c)/s^2 == q,
(-s^2 - s^2 + s^2)/(2 s^2) == p
};

FullSimplify[(15 (-2 q s^4 + 4 (1 + q) s^2 s^2 -
2 (2 + q) s^4 + (s^2 + 3 s^2) s^2 -
s^4))/(4 (b c - b c)^2),
Assumptions -> ListOfAssumptions]

The result is

30 (1 + q)

If I remove from the assumptions list the first assumption (b c
- b c == 2 Area) the result becomes a very large expression.
What should I do in order to not use the assumption b c - b
c == 2 Area ?
(This is important because this is a minimal example from a big set of
expressions).

Thanks,

Carlos Fernandes

```

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