Derivative of Tangent Function (Interactive Investigation)

① This GeoGebra example provides an interactive, guided investigation into the derivative of the tangent function, y = tan(x), by dynamically showing the tangent line's slope at a moving point. ② Core mathematical concepts include derivatives, tangent slopes, trigonometric functions, limits, and the relationship between a function and its derivative graph. ③ Construction uses GeoGebra commands such as Point, Circle, Tangent, Intersect, Vector, Textfield, InputBox, and buttons to create a student-driven exploration environment. ④ It is designed for high school or early college calculus students, serving as a hands-on tool to understand why the derivative of tan(x) is sec²(x) and to build intuition about instantaneous rates of change.