Gateway Arch: Modeling an Isosceles Triangle with Trigonometry and Matrices

①This GeoGebra example constructs a geometric model of the iconic Gateway Arch in St. Louis, demonstrating how mathematical shapes can represent real architectural forms. ②Core concepts include isosceles triangles, trigonometric functions (sine/cosine), matrix transformations, and linear equations, which together define the arch's symmetric curve and structure. ③Construction: Based on the summary, objects a, c, f (likely functions or parameters), points B and A, and image pic1 are used; GeoGebra commands such as function definitions, point coordinates, and matrix operations parameterize the arch shape, with a background image for comparison. ④Suitable for high school or early college students to explore applications of trigonometry and matrices in geometric modeling, or as a cross-disciplinary project linking math and architecture.