The meaning of mathematical symbols
Constant is a fixed value. For example, the ratio of the circumference to the diameter of a circle is π, and the expansion coefficient of iron is 0.0000 12. Constant is a name with a certain meaning, which is used to replace numbers or strings, and its value never changes. In mathematics, a capital c is often used to represent a constant.
Complex number is the conceptual extension of number. We call a number in the form of z = a+bi (both a and b are real numbers) a complex number, where a is called the real part, b is called the imaginary part, and I is called the imaginary part. The set of complex numbers is represented by C, and the set of real numbers is represented by R. Obviously, R is the proper subset of C, and the set of complex numbers is out of order, so the order of size cannot be established.