You can simplify it after the fact with refine, assuming Q.positive(b**2 - a**2). You could also add that assumption to the global assumptions, but that isn't really integrated with anything yet.
Aaron Meurer On Wed, Oct 16, 2013 at 1:32 PM, Pablo Puente <[email protected]> wrote: > Is it possible to define an assumption for an integral? > > Example from Wester test case V8 in Macsyma: > > (c27) /* This example involves several symbolic parameters > => 1/sqrt(b^2 - a^2) log([sqrt(b^2 - a^2) tan(x/2) + a + b]/ > [sqrt(b^2 - a^2) tan(x/2) - a - b]) (a^2 < > b^2) > [Gradshteyn and Ryzhik 2.553(3)] */ > assume(b^2 > a^2)$ > Time= 270 msecs > > (c28) integrate(1/(a + b*cos(x)), x); > Time= 1070 msecs > (b - a) sin(x) 2 2 > -------------- - sqrt(b - a ) > cos(x) + 1 > log(------------------------------) > (b - a) sin(x) 2 2 > -------------- + sqrt(b - a ) > cos(x) + 1 > (d28) - ----------------------------------- > 2 2 > sqrt(b - a ) > > (c29) trigsimp(ratsimp(diff(%, x))); > /aquarius/data2/opt/local/macsyma_422/share/trigsimp.so being loaded. > Time= 1740 msecs > 1 > (d29) ------------ > b cos(x) + a > > > -- > You received this message because you are subscribed to the Google Groups > "sympy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/sympy. > For more options, visit https://groups.google.com/groups/opt_out. -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sympy. For more options, visit https://groups.google.com/groups/opt_out.
