Visualization of Double Integrals with Riemann Sum Approximation

This GeoGebra example demonstrates the geometric interpretation and numerical approximation of the double integral ∬f(x,y)dA. The integration domain is defined on the xy-plane using Polygon and Segment commands, while the integrand surface f(x,y) is rendered via Function and CurveCartesian commands in 3D. The key feature employs Prism and Sequence commands to construct Riemann sum columns: the dom