1. The problem statement, all variables and given/known data How do I show that this integral tends to zero as b tends to a ? 2. Relevant equations [itex]\int_a^b \int_0^a (f(a)-f(y))(x-y)dy(b-x)dx[/itex] 3. The attempt at a solution I'm not sure how to start. Any hints or ideas will be very much appreciated. We are given that function f is continuous over the domain. Thank you.