Re: Evaluating inequalities
- To: mathgroup at smc.vnet.net
- Subject: [mg131578] Re: Evaluating inequalities
- From: William Rummler <wrummler at wolfram.com>
- Date: Sun, 8 Sep 2013 03:05:34 -0400 (EDT)
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- Delivered-to: l-mathgroup@wolfram.com
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Hi Sam,
The relation isn't always true given the assumption:
In[1]:= relation = -k^2 + w^2/KK^2 > 0;
In[2]:= assumption = w/k < KK;
In[3]:= counterExample =
FindInstance[assumption && Not@relation, {w, k, KK}]
Out[3]= {{w -> -1, k -> 1, KK -> 1}}
In[4]:= {assumption, relation} /. counterExample
Out[4]= {{True, False}}
hth,
William
----- Original Message -----
> Hi,
>
> Why doesn't this:
>
> Assuming[w/k < KK, -k^2 + w^2/KK^2 > 0] // Simplify
>
> evaluate to False?
>
> Thanks!
>
> Sam
>
>