On 8/29/2009 6:14:13 PM, lvl107 wrote:
>Hi everyone. My background:
>high school. My language:
>Vietnamese. I am new Mathcad
>user. I was interested in
>solving Pell equation. Please
>help me solving x^2 - 151*y^2
>= 1. I have often got errors
>in Mathcad programming. Please
>check the root: (1728148040 ;
>140634693) and give your
>comment. Thanks again.
_______________________________
Please stop changing thread. If a Mathcad chevron has read your first "Pell", he will not see any of your other ones. Next time, "Save as" as low as Mathcad 8, even an additional as low as Mathcad 6.
Your background is immaterial for this new problem.
The two numbers are the convergent of the SQRT(151), as demonstrated. The Pentium will not give the required accuracy and neither the Mathcad floating point. That ratio goes in a fixed arithmetic machine [just guessing]. I can't help more really because of the lack of interest. Who wants > 15 figures that the Pentium can't render ? To view those numbers, at 15 true decimals a measured distance of 1000000 km the error would be 1mm.
When you get > 20 figures from the symbolic, it is because there is a continued fraction that the Mathcad "Big Number" can crunch. When you get only 20 figures, that is because the Mathcad symbolic explodes the Pentium floating point. Only 17, 18 are considered possibly true, thus the Pentium convention to limit to 15 figures considering the error propagation. Your numbers are in the range above the Pentium, as it looks.
BTW, those numbers, they didn't drop with the last rain, did they ? The source from where they come from should also indicate the linear relationship to other SQRT than the SQRT2, your answer is right there. Even with the source in hand, my answer is that I have no answer because not knowing the linear relationship to other SQRT than SQRT2, and also limited by the Pentium. Again, send an e-mail to either or both Neil Sloane or Simon Plouffe. A bit of why you are asking this solution with such a degree of accuracy would make the readers more willing to devote some time and research. Another point is that I have no knowledge if there would be a software capable from the Pentium to emulate a big blue. In fact there may still be one ... visiting the "Martindale". Years ago, Boris had the emulator and offered me such services for free right from my equations, taking some time to calculate.
jmG