I'm having issues evaluating the definite integral of a symbolic expression using MATLAB's Symbolic Toolbox:
syms t n
assume(n, 'integer')
expression = sin(3*t)^2 * cos(n*t);
value = int(expression, t, -pi, pi);
This returns that the integral is 0 everywhere, despite the fact that there should be a special case where the integral is non-zero at n = 6. When I don't make the assumption that 'n' is an integer, I get an expression that is singular at n = 6. Is there some way that I can adapt my code so that it returns the expected answer? For reference, I go on to take the sum of the integral expressions for increasing values of n using symsum(), and would like to avoid the case where I need to explicitly define these singular values of 'n'. I am trying to avoid evaluating this integral numerically, if at all possible.
