There is a sign bug in limit in the following cases (Maple V Release 4 under Solaris on a Sun workstation):
> limit(42/x/ln(x), x=0, right); -infinity
Ok, that’s right. But:
> limit(c/x/ln(x), x=0, right); signum(c) infinity
The correct result should be -signum(c)*infinity. (Note that not the complex limit should be taken, but the real one). Interestingly, applying a minus sign has no influence on the result:
> limit(-c/x/ln(x), x=0, right); signum(c) infinity
So the result isn’t always wrong. It seems as if the numerator isn’t completely considered if it contains a variable. For example, try 17^e instead of c.
Assuming c to be real has no effect.
It is corrected with Maple 6. (U. Klein)