The facility plane plays an essential role in Mathematics. The is additionally known as z-plane, which is created of two mutually perpendicular lines dubbed axes. The horizontal line represents actual numbers and is recognized as the real axis. On the other hand, the vertical line denotes imagine numbers and also is termed together an imagine axis. The complex plane is supplied to stand for a geometric interpretation of complicated numbers. This aircraft is comparable to the Cartesian aircraft having real and also imaginary parts of a facility number along with X and Y axes. There space two concepts related to complex numbers. They space magnitude and argument. In this article, permit us talk about in detail around the definition, properties, formulas because that the discussion of complex numbers.

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What are complex Numbers?

A complex number is a number the is created as a + ib, in i m sorry “a” is a real number, and also “b” is an imagine number. The facility number has a prize “i” which satisfies the problem i2 = −1. Complex numbers deserve to be described as the extension of the one-dimensional number line. In the complicated plane, a facility number denoted by a + bi is stood for in the kind of the allude (a, b). It is come be detailed that a complex number through zero actual part, such together – i, -5i, etc, is referred to as purely imaginary. Also, a complicated number with zero imaginary component is known as a actual number.

Argument of complex Numbers Definition

The dispute of a complicated number is defined as the edge inclined native the actual axis in the direction the the complex number stood for on the facility plane. That is denoted by “θ” or “φ”. The is measured in the conventional unit dubbed “radians”.


In this diagram, the facility number is denoted by the allude P. The length OP is recognized as magnitude or the modulus the a number, if the angle at i m sorry OP is inclined native the positive real axis is stated to it is in the dispute of the suggest P.

Argument of complicated Numbers Formula

In polar form, a complicated number is stood for by the equation r(cos θ + ns sin θ), here, θ is the argument. The argument function is denoted by arg(z), whereby z denotes the complex number, i.e. Z = x + iy. The computation that the complicated argument can be excellent by using the adhering to formula:

arg (z) = arg (x+iy) = tan-1(y/x)

Therefore, the dispute θ is stood for as:

θ = tan-1 (y/x)

Properties of debate of complex Numbers

Let us comment on a few properties mutual by the debates of complex numbers. Intend that z it is in a nonzero complex number and also n be part integer, then

arg(zn) = n arg(z)

Let united state assume, z1 and z2 be the two complex numbers, the adhering to identities are:

arg (z1/ z2) = arg ( z1) – arg ( z2)arg ( z1 z2) = arg ( z1) + arg ( z2)

How to find the argument of facility Numbers?

Find the real and imaginary parts from the given complicated number. Represent them as x and y respectively.Substitute the worths in the formula θ = tan-1 (y/x)Find the value of θ if the formula gives any standard value, otherwise compose it in the kind of tan-1 itself.This value complied with by the unit “radian” is the forced value of complicated argument because that the given facility number.



Find the discussion of the facility number 2 + 2√3i.


Let z = 2 + 2√3i.

Here, the actual part, x = 2

Imaginary part, y = 2√3

We recognize that the formula to find the discussion of a facility number is

arg (z) = tan-1(y/x)

arg (z) = tan-1(2√3/2)

arg (z) = tan-1(√3)

arg (z) = tan-1(tan π/3)

arg (z) = π/3

Therefore, the argument of the complex number is π/3 radian.

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