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Vladimir Bondarenko
Posted: Mon Jun 04, 2007 9:51 pm
Guest
Hello computer algebra artists,

Is there a soul who can show in CAS steps how
to get to the exact value of this integral

int((sqrt(4-3*z^2)*sqrt(9-12*z^2)
+ I*sqrt(4-z^2)*sqrt(9-12*z^2)
- I*sqrt(4-z^2)*sqrt(12-9*z^2) )
/sqrt(144-480*z^2+555*z^4-255*z^6+36*z^Cool,
z= 0..1);

?

Best wishes,

Vladimir Bondarenko

VM and GEMM architect
Co-founder, CEO, Mathematical Director

http://www.cybertester.com/ Cyber Tester, LLC
http://maple.bug-list.org/ Maple Bugs Encyclopaedia
http://www.CAS-testing.org/ CAS Testing
Thomas Richard
Posted: Tue Jun 05, 2007 9:49 am
Guest
Vladimir Bondarenko <vb@cybertester.com> wrote:

Quote:
Hello computer algebra artists,

Is there a soul who can show in CAS steps how
to get to the exact value of this integral

int((sqrt(4-3*z^2)*sqrt(9-12*z^2)
+ I*sqrt(4-z^2)*sqrt(9-12*z^2)
- I*sqrt(4-z^2)*sqrt(12-9*z^2) )
/sqrt(144-480*z^2+555*z^4-255*z^6+36*z^Cool,
z= 0..1);

A:=int((sqrt(4-3*z^2)*sqrt(9-12*z^2)
+ I*sqrt(4-z^2)*sqrt(9-12*z^2)
- I*sqrt(4-z^2)*sqrt(12-9*z^2) )
/sqrt(144-480*z^2+555*z^4-255*z^6+36*z^Cool,
z= 0..1);
F:=factor(A);
J:=convert(F,'Int');
combine(J); # optionally
value(%);

--
Thomas Richard
Maple Support
Scientific Computers GmbH
http://www.scientific.de
Mate
Posted: Tue Jun 05, 2007 10:37 am
Guest
On Jun 5, 5:51 am, Vladimir Bondarenko <v...@cybertester.com> wrote:

Quote:

int((sqrt(4-3*z^2)*sqrt(9-12*z^2)
+ I*sqrt(4-z^2)*sqrt(9-12*z^2)
- I*sqrt(4-z^2)*sqrt(12-9*z^2) )
/sqrt(144-480*z^2+555*z^4-255*z^6+36*z^Cool,
z= 0..1);

ans := 0;

Hint: Int(f,0..1) = Int(f,0..sqrt(3)/2) + Int(f,sqrt(3)/2..1)

Mate
dimitris
Posted: Tue Jun 05, 2007 2:14 pm
Guest
Hi.

$VersionNumber
5.2

In[14]:=
Integrate[(Sqrt[4 - 3*z^2]*Sqrt[9 - 12*z^2] + I*Sqrt[4 - z^2]*Sqrt[9 -
12*z^2] - I*Sqrt[4 - z^2]*Sqrt[12 - 9*z^2])/
Sqrt[144 - 480*z^2 + 555*z^4 - 255*z^6 + 36*z^8], {z, 0, 1}]
Developer`ZeroQ[%]

Out[14]=
(1/6)*(2*I*Sqrt[3]*EllipticF[Pi/3, 4/3] - 3*I*EllipticF[ArcSin[2/
Sqrt[3]], 3/4] + 3*EllipticK[1/4])

Out[15]=
True

Dimitris

/ Vladimir Bondarenko :
Quote:
Hello computer algebra artists,

Is there a soul who can show in CAS steps how
to get to the exact value of this integral

int((sqrt(4-3*z^2)*sqrt(9-12*z^2)
+ I*sqrt(4-z^2)*sqrt(9-12*z^2)
- I*sqrt(4-z^2)*sqrt(12-9*z^2) )
/sqrt(144-480*z^2+555*z^4-255*z^6+36*z^Cool,
z= 0..1);

?

Best wishes,

Vladimir Bondarenko

VM and GEMM architect
Co-founder, CEO, Mathematical Director

http://www.cybertester.com/ Cyber Tester, LLC
http://maple.bug-list.org/ Maple Bugs Encyclopaedia
http://www.CAS-testing.org/ CAS Testing
Daniel Lichtblau
Posted: Tue Jun 05, 2007 3:08 pm
Guest
On Jun 5, 2:14 pm, dimitris <dimmec...@yahoo.com> wrote:
Quote:
Hi.

$VersionNumber
5.2

In[14]:=
Integrate[(Sqrt[4 - 3*z^2]*Sqrt[9 - 12*z^2] + I*Sqrt[4 - z^2]*Sqrt[9 -
12*z^2] - I*Sqrt[4 - z^2]*Sqrt[12 - 9*z^2])/
Sqrt[144 - 480*z^2 + 555*z^4 - 255*z^6 + 36*z^8], {z, 0, 1}]
Developer`ZeroQ[%]

Out[14]=
(1/6)*(2*I*Sqrt[3]*EllipticF[Pi/3, 4/3] - 3*I*EllipticF[ArcSin[2/
Sqrt[3]], 3/4] + 3*EllipticK[1/4])

Out[15]=
True

Dimitris

The zero testing uses numeric approximation. So this gives a
plausibility argument but not a rigorous proof.

Daniel Lichtblau
Wolfram Research



Quote:
/ Vladimir Bondarenko :

Hello computer algebra artists,

Is there a soul who can show in CAS steps how
to get to the exact value of this integral

int((sqrt(4-3*z^2)*sqrt(9-12*z^2)
+ I*sqrt(4-z^2)*sqrt(9-12*z^2)
- I*sqrt(4-z^2)*sqrt(12-9*z^2) )
/sqrt(144-480*z^2+555*z^4-255*z^6+36*z^Cool,
z= 0..1);

?

Best wishes,

Vladimir Bondarenko

VM and GEMM architect
Co-founder, CEO, Mathematical Director

http://www.cybertester.com/ Cyber Tester, LLC
http://maple.bug-list.org/ Maple Bugs Encyclopaedia
http://www.CAS-testing.org/ CAS Testing
dimitris
Posted: Tue Jun 05, 2007 3:35 pm
Guest
Hi Daniel.

I was prety sure about that.

In fact in another similar response I point
out also myself it!

But having spent at least two hours "playing" with these,
and failed to simplify to zero (A really hard task!)
I tried Developer`ZeroQ[..] due to my desperate
situation!

Anyway...I give up!

Dimitris

/ Daniel Lichtblau :
Quote:
On Jun 5, 2:14 pm, dimitris <dimmec...@yahoo.com> wrote:
Hi.

$VersionNumber
5.2

In[14]:=
Integrate[(Sqrt[4 - 3*z^2]*Sqrt[9 - 12*z^2] + I*Sqrt[4 - z^2]*Sqrt[9 -
12*z^2] - I*Sqrt[4 - z^2]*Sqrt[12 - 9*z^2])/
Sqrt[144 - 480*z^2 + 555*z^4 - 255*z^6 + 36*z^8], {z, 0, 1}]
Developer`ZeroQ[%]

Out[14]=
(1/6)*(2*I*Sqrt[3]*EllipticF[Pi/3, 4/3] - 3*I*EllipticF[ArcSin[2/
Sqrt[3]], 3/4] + 3*EllipticK[1/4])

Out[15]=
True

Dimitris

The zero testing uses numeric approximation. So this gives a
plausibility argument but not a rigorous proof.

Daniel Lichtblau
Wolfram Research



/ Vladimir Bondarenko :

Hello computer algebra artists,

Is there a soul who can show in CAS steps how
to get to the exact value of this integral

int((sqrt(4-3*z^2)*sqrt(9-12*z^2)
+ I*sqrt(4-z^2)*sqrt(9-12*z^2)
- I*sqrt(4-z^2)*sqrt(12-9*z^2) )
/sqrt(144-480*z^2+555*z^4-255*z^6+36*z^Cool,
z= 0..1);

?

Best wishes,

Vladimir Bondarenko

VM and GEMM architect
Co-founder, CEO, Mathematical Director

http://www.cybertester.com/ Cyber Tester, LLC
http://maple.bug-list.org/ Maple Bugs Encyclopaedia
http://www.CAS-testing.org/ CAS Testing
Axel Vogt
Posted: Tue Jun 05, 2007 3:55 pm
Guest
Daniel Lichtblau wrote:
Quote:
On Jun 5, 2:14 pm, dimitris <dimmec...@yahoo.com> wrote:
Hi.

$VersionNumber
5.2

In[14]:=
Integrate[(Sqrt[4 - 3*z^2]*Sqrt[9 - 12*z^2] + I*Sqrt[4 - z^2]*Sqrt[9 -
12*z^2] - I*Sqrt[4 - z^2]*Sqrt[12 - 9*z^2])/
Sqrt[144 - 480*z^2 + 555*z^4 - 255*z^6 + 36*z^8], {z, 0, 1}]
Developer`ZeroQ[%]

Out[14]=
(1/6)*(2*I*Sqrt[3]*EllipticF[Pi/3, 4/3] - 3*I*EllipticF[ArcSin[2/
Sqrt[3]], 3/4] + 3*EllipticK[1/4])

Out[15]=
True

Dimitris

The zero testing uses numeric approximation. So this gives a
plausibility argument but not a rigorous proof.

Daniel Lichtblau
Wolfram Research


Do not know MMA, but can you 'imitate' Thomas Richard's solution?


Quote:



/ Vladimir Bondarenko :

Hello computer algebra artists,
Is there a soul who can show in CAS steps how
to get to the exact value of this integral
int((sqrt(4-3*z^2)*sqrt(9-12*z^2)
+ I*sqrt(4-z^2)*sqrt(9-12*z^2)
- I*sqrt(4-z^2)*sqrt(12-9*z^2) )
/sqrt(144-480*z^2+555*z^4-255*z^6+36*z^Cool,
z= 0..1);
?
Best wishes,
Vladimir Bondarenko
VM and GEMM architect
Co-founder, CEO, Mathematical Director
http://www.cybertester.com/ Cyber Tester, LLC
http://maple.bug-list.org/ Maple Bugs Encyclopaedia
http://www.CAS-testing.org/ CAS Testing

 
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