Forums before death by AOL, social media and spammers... "We can't have nice things"
|    sci.math.symbolic    |    Symbolic algebra discussion    |    10,432 messages    |
[   << oldest   |   < older   |   list   |   newer >   |   newest >>   ]
|    Message 9,796 of 10,432    |
|    clicliclic@freenet.de to clicliclic@freenet.de    |
|    Re: More teething help    |
|    29 Jan 18 06:38:23    |
      clicliclic@freenet.de schrieb:       >       > Thanks to the (still unpublished?) Masser-Zanier counterexample Waldek       > informed us about, we know that there are infinitely many (though       > increasingly complicated algebraic) u^2 for which       >       > INT(x/((x^2 - u^2)*SQRT(x^3 - x)), x)       >       > has a solution (also of increasing complexity) in terms of elementary       > functions. Consequently, via the usual Moebius transformation of the       > integration variable, there are also infinitely many v = (u^2 - 1)/       > (u^2 + 1) for which       >       > INT((y^2 - 1)/((y^2 + 2*v*y + 1)*SQRT(y^4 - 1)), y)       >       > has such an elementary solution. I too expect these patterns to be       > exceptions rather than the rule, the rule being that the number of       > pseudo-elliptic cases is finite and small. But does this pair already       > exhaust the store of patterns involving simple square-root radicands       > and giving rise to infinitely many pseudo-elliptic integrals?       >              The above relies on the transformation x = #i*(1 - y)/(1 + y).       Alternatively one may put x = z^2 to obtain:               INT(z^2/((z^4 - w^4)*SQRT(z^4 - 1)), z)              where w^2 = u. Now we have three simple patterns of this kind already.              Martin.              --- SoupGate-Win32 v1.05        * Origin: you cannot sedate... all the things you hate (1:229/2)    |
[   << oldest   |   < older   |   list   |   newer >   |   newest >>   ]
(c) 1994, bbs@darkrealms.ca