Hi there, integrate() seems to have a bug which leads to wrong answers for rational trigonometric functions. E.g.
In [7]: integrate(1/(cos(x)+2),(x,0,2*pi)) Out[7]: 0 It's obvious that the answer is wrong: the function is strictly positive everywhere, so integral cannot be 0. It seems (I didn't check it) that SymPy uses trigonometric substitution like u=tan x/2 and then incorrectly substitute 0 and 2*pi as limits. (There are singular points in the interval (0,2*pi) for tan x/2, so it does not work.) See an issue on the tracker: http://code.google.com/p/sympy/issues/detail?id=3179 Thanks! -- Sincerely yours, Ilya V. Schurov. -- You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
