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Re: "Nice" complex form

  • To: mathgroup at smc.vnet.net
  • Subject: [mg131602] Re: "Nice" complex form
  • From: Alexei Boulbitch <Alexei.Boulbitch at iee.lu>
  • Date: Tue, 10 Sep 2013 03:46:35 -0400 (EDT)
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Hi,

Can I get

Assuming[a - 4 < 0, Sqrt[a - 4]]

to "simplify" to

I Sqrt[4 - a]

?

Thanks,

Sam


Hi, Sam,

You can.


Assuming[x > 0,
  Simplify[Sqrt[a - 4] /. a -> 4 - x,
   ComplexityFunction -> (Count[{#1}, Times[-1, _], Infinity] &)]] /.
 x -> 4 - a

I Sqrt[4 - a]

Have fun, Alexei


Alexei BOULBITCH, Dr., habil.
IEE S.A.
ZAE Weiergewan,
11, rue Edmond Reuter,
L-5326 Contern, LUXEMBOURG

Office phone :  +352-2454-2566
Office fax:       +352-2454-3566
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e-mail: alexei.boulbitch at iee.lu





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