Activity 3.5.2 - Trapezoid

①This example demonstrates the relationship between the area of a trapezoid and Riemann sums (upper and lower sums), providing a visual approach to approximating areas under curves in integral calculus. ②Core mathematical concepts include trapezoids, definite integrals, Riemann sums, expected value, and numerical approximation in probability, emphasizing the use of trapezoidal approximations for area. ③Construction details: using GeoGebra commands such as Segment, Line, Point, Polygon, Intersect, and Angle, the example builds a trapezoid with objects like points A, P, R, segments a, b, d, polygon poly1, and angle α, allowing interactive exploration of area changes. ④Suitable for high school to early college students, this activity serves as an introductory tool for calculus lessons or as a visual aid for expected value in probability, useful for classroom demonstrations or self-study.