Comment #10 on issue 2849 by smi...@gmail.com: integration of cos(x)/sin(x)**n
http://code.google.com/p/sympy/issues/detail?id=2849
factoring the expression in comment 4 might work, but the replacement is rejected by the test at L1680 in master (as of the date of this post). If that test is altered to only take a new expression if it is shorter in count ops then one obtains
factor(diff(integrate(cos(x)/sin(x)**7, x), x))
sin(x)*cos(x)/((cos(x) - 1)**4*(cos(x) + 1)**4)
trigsimp(_)
cos(x)/sin(x)**7 BUT this also allows changes like the following:
eq = cos(2)*(cos(3) + 1)**2/(cos(3) - 1)**2 trigsimp(eq)
sin(3)**4*cos(2)/(-cos(3) + 1)**4 So a better exclusion mechanism (along with factoring) is needed. -- You received this message because you are subscribed to the Google Groups "sympy-issues" group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
