An integral finds volume by adding infinitely many very thin slices.
- Start with a curve y = f(x). This curve represents how the radius of the shape changes along the x-axis.
- Imagine slicing the shape into very thin pieces along the x-direction.
- Each slice is so thin that its thickness is called dx.
- Each thin slice looks like a flat circular disk.
- The radius of the disk is f(x). The volume of one tiny disk is found using the circle formula:
area × thickness = π(f(x))² dx.
- The integral means adding up all these tiny disk volumes along the x-axis.
When all the tiny disks are added together, they form the entire 3D solid.
Now, do you understand how integrals work?