Complex Numbers: A complex number is a number in the form z = a + bi, where a is the real part and b is the imaginary part. On the Argand plane, the complex number is represented as a point with coordinates (a, b).
Modulus: The modulus of a complex number z = a + bi is given by |z| = √(a² + b²).
Argument: The argument of a complex number z = a + bi is the angle θ formed by the line connecting the point (a, b) with the origin (0, 0). It is given by θ = tan⁻¹(b/a).