Copy of Rotating a Parabola Around the x-axis

Drag point A (the [color=#00FF00]GREEN[/color] point) and see the result of rotating the parabola [math]f(x) = 4x-x^{2}[/math] around the x-axis.
– okumura0518, Steve Phelps

Information: Copy of Rotating a Parabola Around the x-axis