"integrate" yields incorrect results on some rational

functions.

"Division by 0" is strange.

The definite integral below is certainly greater than 0

as the integrand is positive over [0, 1]. "integrate

(1/((x-3)^4+1/2), x)" returns the noun form, so maybe

(maybe) what happens is that the noun form is evaluated

at the limits of integration and it's the same, hence 0

is the result. (Just guessing there.)

Note that the difference between the two integrands is

that one is 1/(something + 1), while the other is

1/(same something + 1/2).

----------------------------------------

(%i1) integrate (1/((x-3)^4+1), x, 0, 1);

Division by 0

-- an error. Quitting. To debug this try

DEBUGMODE(TRUE);

(%i2) integrate (1/((x-3)^4+1/2), x, 0, 1);

(%o2) 0

(%i3) build_info ();

Maxima version: 5.9.1

Maxima build date: 21:24 9/23/2004

host type: i686-pc-linux-gnu

lisp-implementation-type: CMU Common Lisp

lisp-implementation-version: 19a

----------------------------------------

Same behavior observed in CVS build of 2004/11/24.