I am giving the following input to Ti-89 Titanium:
limit(S((2 x cos(100 x Pi x t)+2 x sin(10 x Pi x t))2 ,t,-t1,t1)/(2 x t1),t1,inf)
where S is the integral symbol, Pi is π = 3.14, x is the multiplication symbol and inf is the infinity symbol
The TI-89 answer is undef
If I do it by hand it...