In addition:

The problem is that Maxima simplifies (x^a)^b --> x^(a*b), when x is positive, but this condition is not enough to be correct in general. This is an example:

(%i2) assume(x>0)$

(%i3) (x^a)^b;

(%o3) x^(a*b)

This type of simplification is correct only if one of the following conditions holds:

(1) b an integer (correctly implemented) or

(2) -1 < a <= 1 (not implemented) or

(3) -%pi < imagpart(a*log(x)) <= %pi (not implemented)

Dieter Kaiser