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Topic: Numerical expression
Replies: 6   Last Post: Nov 28, 2012 3:16 AM

 Messages: [ Previous | Next ]
 Alexei Boulbitch Posts: 483 Registered: 2/28/08
Re: Numerical expression
Posted: Nov 27, 2012 3:51 AM

How could I handle in Mathematica this expression?

( ( 9(3)^1/2+4(23)^1/2)^1/3 + (9(3)^1/2+4(23)^1/2)^1/3 ) / (3)^1/2)

With a lot of trouble I have found out that is equal 1,
but how to get it with Mathematica?

Thanks very much.

Hi, Massimo,

The expression that you have written here does not look to have sense. Just evaluate this in Mathematica:

((Defer@(((9 ((3)^1)?2+4 ((23)^1)?2)^1)?3+((9 ((3)^1)?2+4 ((23)^1)?2)^1)?3))?((3)^1))?2

Is it what you had in mind? If yes, you can evaluate it straightforwardly:

((9 (3)^1/2 + 4 (23)^1/2)^1/3 + (9 (3)^1/2 + 4 (23)^1/2)^1/3)/(3)^1/
2 // FullSimplify

That's what you get out:

119/18

It seems that you may have had in mind this (evaluate it):

Defer@((9 (3)^(1/2) + 4 (23)^(1/2))^(1/3) + (9 (3)^(1/2) +
4 (23)^(1/2))^(1/3))/(3)^(1/2)

If yes, it also can be directly evaluated:

((9 (3)^(1/2) + 4 (23)^(1/2))^(1/3) + (9 (3)^(1/2) + 4 (23)^(1/2))^(1/
3))/(3)^(1/2) // FullSimplify

yielding

1 + Sqrt[23/3]

but not 1. Probably you have had something else in mind.

Have fun, Alexei

Alexei BOULBITCH, Dr., habil.
IEE S.A.
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e-mail: alexei.boulbitch@iee.lu

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