Centroid of a planar region and planar curve

In this figure a segment of a parabola is graphed. You can reshape it by dragging the three control points.[br][br]Selecting the first checkbox will connect the two endpoints and create a [b]parabolic region[/b]. The centroid, [b][i]R[/i][/b], of this region is displayed. [br][br]Selecting the second checkbox takes only the [b]parabolic curve[/b] itself into account and displays [b][i]C[/i][/b], the centroid of the curve.

Information: Centroid of a planar region and planar curve