Thanks for the help! You are right, sorry for the mistake, Ixx[t] is Ixx; e this also aplies to Iyy and Izz.
However, I've tried to use it and still isn't what I want as an answer.
To put in other example,...
Let's say that I have this expression:
y = A*Cos [\[Theta]] + (B/A)*Sin[\[Theta]] + (B*A)*x +
A*Tan[x] + (B/A)*x^2
And, what I want to know is how to rewrite it like this, using Mathematica methods:
y = A*(Cos [\[Theta]]+Tan[x]) + (B/A)*(Sin[\[Theta]]+x^2) + (B*A)*x
Because I want "y" as a sum of the constant terms {A,B} in any combination between them, but also multiplying a function that do not include them, like above.
For example, this format o y, applying Apart for "B"
Apart[ y , {B}]
Results in:
{(B (A^2 x + x^2 + Sin[\[Theta]]))/A + A (Cos[\[Theta]] + Tan[x])}
Which doesn't help, because the first polynomial term contains "A", that I want only as a coefficient.
Thanks again for the help.
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