Maxima can't integrate 1/(cos(x)+sin(x))



Dear Felix,

Many sincere thanks for your message. I have also several
complaints with the Maxima manuals, but I try to study them
as much as possible when I find time.

With respect to defint and ldefint, these are different commands
according to the documentation. This is also clear from the short
Maxima session below. (Therefore, I cannot agree with your
related comment.)

(C1) display2d : false$
(C2) ldefint(1/(cos(x)+sin(x)),x,0,%pi/4);
(D2) LOG(SQRT(2)/(SQRT(2)-1)+1/(SQRT(2)-1))/SQRT(2)
       -LOG(2/SQRT(2)+1)/SQRT(2)
(C3) defint(1/(cos(x)+sin(x)),x,0,%pi/4);
(D3) 'INTEGRATE(1/(SIN(x)+COS(x)),x,0,%PI/4)
(C4) intanalysis : false$
(C5) defint(1/(cos(x)+sin(x)),x,0,%pi/4);
(D5) SQRT(2)*LOG(2*SQRT(2)+3)/2
       -SQRT(2)*LOG(SQRT(2)+1)/2

You can also use describe(defint); and reply to the question mark with all;

When Maxima asks too many questions, to be sincere, I use the option
assume_pos : true although I know frequently this is not permissible 
from the mathematical point of view. Sometimes, Maxima's questions
are not expected at all, for example for trigonometric functions. 
Naturally, I completely agree with your comment in your message
of April 10, 2003.

Many thanks again and best regards,

Nikos