This is t is equal to b. So we're saying that it is continuous. It is continuous over this whole interval. Now, for fun, let's define a function capital F of x. And I will do it in blue. Let's define capital F of x as equal to the definite integral from a, from a as a lower bound, to x of f of t, of f of t, dt, where x is in this interval. Where a is less than or equal to x is less than or equal to b.