Why does the following not get simplified?

simplify(conjugate(b) * I - conjugate(a) + conjugate(b*I+a));

It seems Maple does not know conjugation is linear, since the following

simplify(conjugate(b) * I                + conjugate(b*I  ));
simplify(                 - conjugate(a) + conjugate(    a));

do get simplified to 0.

The function does simplify to 0, but it assumes my and are real, which they are not. 

Why does the following code 

evalb(a * conjugate(a) = abs(a) ^ 2);

not produce true?

Dear all,

Using  I can suppress the dependency of  in the differential equation  in the output when I type . 

However, when I want to export the output to LaTeX or MathML using  and , the dependency on  is still there!

How to remove the dependency on ?

Thank you!