The following product

(product(mu^x[i]/factorial(x[i]), i = 1 .. n))

does not simplify to the most obvious form whatever I try

mu^(sum(x[i], i = 1 .. n))/(product(factorial(x[i]), i = 1 .. n))

What can it be?

The following command works fine until you use it in the combination conjugate and diff.

example in Physics:

declare(phi(X));

diff(conjugate(phi(X)),x1);

phi(X) should now appear as phi with index x1 and a bar only, but

it comes as phi(X) x1 , the declare command is not effective. Non conjugate works fine.

Any idea - thanks in advance