Question: Summations

I have a calculation (analytic) involving sums (finite) that ends up with an expression structured like a sum over an expression with several terms, like

sum(Y(t)*cos(omega*t) + a*sin(omega*t)+b*cos(omega*t),t);

(The real case is more involved but this simple example shows the issue.)

What I want is to distribute the sum over each term separately, observing that a & b are numbers & therefore can be pulled out of the sum. Note that the expression being summed over is the result of another operation and therefore I cannot do the distribution by hand. The result will be used in a set of equations to be solved for the numbers like a or b (as function of said sums). I am not interested in any actual evaluation or reduction of the sums (at this point).

I run Maple 15 on Mac PPC; although this is not a version-specific question.

Thanks for any insight,

Mac Dude