ASKSAGE: Sage Q&A Forum - Latest question feedhttp://ask.sagemath.org/questions/Q&A Forum for SageenCopyright Sage, 2010. Some rights reserved under creative commons license.Mon, 14 Dec 2015 08:41:29 -0600Logarithms and desolvehttp://ask.sagemath.org/question/31560/logarithms-and-desolve/ More questions about desolve results:
Using
y = function('y', x)
desolve(diff(y,x) == y*(100-y), y)
results in the solution:
-1/100*log(y(x) - 100) + 1/100*log(y(x)) == _C + x
But that solution does not work for y<100. But it is correct if you assume that it should be log(abs(y(x)-100)) in the first term. Is the abs() implicit?
(The log terms actually comes from the integral of 1/y and 1/(100-y) so it should be absolute values.)AndersMMon, 14 Dec 2015 08:41:29 -0600http://ask.sagemath.org/question/31560/