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Author Comment/Response
Helmut
09/30/10 04:29am

Hi all,

I've got some trouble right now with complex numbers ! A combination of Assuming[] and Re[] doesn't provide the answer expected.

input :
f[z_] := z/Sqrt[z^2 - a^2]
ff = f[x1]
fff = Assuming[
Element[a, Reals] && Element[x1, Reals] && a > 0 && x1 > 0 &&
x1 > a, Re[ff]]

which leads to :
Re[x1/Sqrt[-a^2 + x1^2]]

where the expected answer is :
x1/Sqrt[-a^2 + x1^2]

Has anybody an idea about how Mathematica should be handled ?

Thanks,
Helmut

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Subject (listing for 'Real Part')
Author Date Posted
Real Part Helmut 09/30/10 04:29am
Re: Real Part Daniel Z-S 09/30/10 12:31pm
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