Now what I want to do in this video is introduce a third value, c, that is in between a and b. And it could be equal to a or it could be equal to b. So let me just introduce it. Write it just like that. And I could write that a is less than or equal to c, which is less than or equal to b. And what I want to think about is, how does this definite integral relate to the definite integral from a to c and the definite integral from c to b? So let's think through that.