Re: Why doesn't TrueQ return True here?
- To: mathgroup at smc.vnet.net
- Subject: [mg119745] Re: Why doesn't TrueQ return True here?
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Mon, 20 Jun 2011 08:05:06 -0400 (EDT)
- Reply-to: hanlonr at cox.net
??$Assumptions
$Assumptions is the default setting for the Assumptions option used in such functions as Simplify, Refine and Integrate. =C2 >>
$Assumptions=True
TrueQ is not one of the functions that makes use of $Assumptions.
$Assumptions = t2 > t1;
Simplify[(t2 - t1) > 0]
True
TrueQ[Simplify[(t2 - t1) > 0]]
True
Bob Hanlon
---- Jacare Omoplata <walkeystalkey at gmail.com> wrote:
=============
Here's the output.
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In[29]:= Element[{t1, t2}, Reals]
Out[29]= (t1 | t2) \[Element] Reals
In[30]:= $Assumptions = t2 > t1
Out[30]= t2 > t1
In[31]:= TrueQ[(t2 - t1) > 0]
Out[31]= False
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I would expect TrueQ to return True, not False. Why does it return False?
And how can I test whether t2-t1 is positive?
Thanks.