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Offline scb  
#1 Posted : 08 April 2009 19:33:14(UTC)
scb

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Thank you for a great program, which I am beginning to learn to use. But I have come upon a problem trying to solve a rather simple equation: x^6 - 6 = 9. Using either one of the two methods I correctly get two roots, of which the first is correct, i.e: 1,5704, but the other is -3,1629 which is obviously wrong.
I am using the program on a Dell Axim x51v in main memory.
Another issue: is there a manual somewhere, or do we have to learn to use the program by doing calculations with it ?

Yours

scb

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Offline Andrey Ivashov  
#2 Posted : 08 April 2009 20:37:44(UTC)
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Hello.

scb wrote:
Using either one of the two methods I correctly get two roots, of which the first is correct, i.e: 1,5704, but the other is -3,1629 which is obviously wrong.

I've tried your example and didn't find any observations. Here is a pic:

Please, describe here, what should I do to get such wrong answer as you figured out.

scb wrote:
Another issue: is there a manual somewhere, or do we have to learn to use the program by doing calculations with it ?

Unfortunately yes. SMath Studio has no any Manual yet. I can just advise you to take a look to the SMath Studio Samples Forum for the first steps.
Offline scb  
#3 Posted : 08 April 2009 21:51:53(UTC)
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I am using the Handheld version on my Dell Axim x51v, could there be a problem solely with the PDA version (WM5) ?
Yours
scb
Offline Andrey Ivashov  
#4 Posted : 08 April 2009 22:55:25(UTC)
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I've checked your example on my device - no problems.
Are you using SMath Studio 0.78?
Offline scb  
#5 Posted : 08 April 2009 23:31:51(UTC)
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I'm using 0.78, but I will try reinstalling and let you know.
Offline scb  
#6 Posted : 09 April 2009 00:10:30(UTC)
scb

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Well, I tried to download your program again and reinstall, and this seems to have solved the problem.
Offline scb  
#7 Posted : 22 April 2009 13:43:36(UTC)
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I've looked into this again, and I've found, that if I change the roots range in options from "-20 to +20" to "-100 to +100" I can reproduce the answer I first came up with : 1,5704 and -3,1629. Is this wrong using of the solve function ???
Offline gimmick  
#8 Posted : 03 August 2009 17:14:03(UTC)
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Here's the same results from Maxima and Wolfram Alpha.



Offline omorr  
#9 Posted : 03 August 2009 18:31:59(UTC)
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scb wrote:
I've looked into this again, and I've found, that if I change the roots range in options from "-20 to +20" to "-100 to +100" I can reproduce the answer I first came up with : 1,5704 and -3,1629. Is this wrong using of the solve function ???


You are right scb. Here is the result in v0.82

This must be a bug?

In addition, gimmick gave the "solve" but in wellknown Symbolic engines like Maxima and Mathematica which gives both real and complex results. Unfortunately, Solve in SMath is a numerical (not symbolical) routine and tries to find only real roots numerically (result are real numbers not expressions). Actually, if you would try to solve this symbolically you will get this?


Regards,
Radovan

Edited by user 03 August 2009 18:40:26(UTC)  | Reason: Not specified

When Sisyphus climbed to the top of a hill, they said: "Wrong boulder!"
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