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Author Comment/Response
Bill Simpson
10/24/12 3:19pm

In Response To 'Re: Re: Undefined'
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You have

24+25x+4 Sqrt[10] Sqrt[4-25y]-75y >0
&&
-24-25x+4 Sqrt[10] Sqrt[4-25y]+75y >0
&&
y < 4/25

and you want to substitute {x->1,y->2}.

That gives

In[1]:= 24+25x+4 Sqrt[10] Sqrt[4-25y]-75y/.{x->1,y->2}

Out[1]= -101+(8*I)*Sqrt[115]

In[2]:= -24-25x+4 Sqrt[10] Sqrt[4-25y]+75y/.{x->1,y->2}

Out[2]= 101 + (8*I)*Sqrt[115]

and you want to know whether each of those complex numbers is greater than zero, but there is no way to answer whether a complex is greater than or even less than zero.

That is why you are getting the error message.

What are you really trying to accomplish?

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Subject (listing for 'Undefined')
Author Date Posted
Undefined PhysicsGuy 10/22/12 2:33pm
Re: Undefined Bill Simpson 10/23/12 8:17pm
Re: Re: Undefined PhysicsGuy 10/24/12 12:00pm
Re: Re: Re: Undefined Bill Simpson 10/24/12 3:19pm
Re: Re: Re: Re: Undefined PhysicsGuy 10/24/12 7:45pm
Re: Re: Re: Re: Undefined PhysicsGuy 10/24/12 9:00pm
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