Geometric Demonstration of Complex Number Subtraction

① This example visually demonstrates the subtraction of two complex numbers on the complex plane by interpreting it as vector subtraction. ② Core mathematical concepts include the algebraic and geometric representation of complex numbers, real and imaginary parts, vector addition and subtraction, and the complex coordinate system. ③ Construction highlights: GeoGebra commands ComplexVector (to create complex vectors), ComplexAddition (used with a negative vector to perform subtraction), and Segment (to draw connecting segments); key objects are z_1, z_2, u, v, C, C_1, w, z, a, b. ④ Suitable for high‑school complex‑number lessons, introductory college complex analysis, and self‑study or classroom demonstration.