I am on the introduction of integral and antiderivative of finding area under curve.
The book didn't tell me why (that's for later), but it only says that the anti-derivative the continuous function is the area under the curve. And when we take the anti-derivative, we are left to determine what the constant term is. On finding the C term, the book reminds that its decision to use the right end point of the upper side of the triangle (in the method of exhaustion) now becomes an advantage, because when we choose to determine the area on [0,0], the rectangular area reduces to a single point and has no area. Thus, A(0)=0 can be used to determine C.
But I wonder why it's advantageous to choose the right end point but no the left one. If we choose the left one, then the area would become a line, like a degenerate rectangle, which too had area of 0.
