Jeremy Bos
MA4635 Final 5.2)3)a)

Because of the symmetry on x=t, the intgeral can be evaluated on one half of the triangle and then the value doubled.

2*(∫_0^(π/2))(∫_0^t)(((Sin[x] 
                    Cos[t]))^2) \[DifferentialD]x \[DifferentialD]t

The Kernel is square integrable.