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Modulus Of Complex Number

The modulus of a complex number is indeed the distance between the point of origin to the point on the approach that has allowed the plane that represents the complex number z. The formula is: z = a + ib

In the argand plane, the modulus of a complex number is indeed the distance between it and its origin. The non-negative value (x2 + y2) is termed the modulus of complex number (z = x + iy) if z = x + iy is a complex number with real x and y and i=√-1. The absolute value of a complex number is indeed known as the modulus of the complex number.

In this post, we will learn how to visually understand the notion of modulus of complex numbers algebraic expressions and its formula and several solved cases.

What is a Complex Number’s Modulus?

The actual and imaginary section’s square root sum of squares of a complex number is the modulus of the complex number. When z is a complex number, its modulus is defined as [Re(z)]2 + [Im(z)]2 and symbolised by |z|. The distance between the centre (0, 0) and the location (a, b) in the complex plane is defined by the modulus of a complex number z = a + ib. Because the distance is the modulus of a complex number, its value always is non-negative.The non-negative value (x2 + y2) is termed the modulus of complex number (z = x + iy) if z = x + iy is a complex number with real x and y and I = -1. The absolute value of a complex number is indeed known as the modulus of the complex number.

Formulae for the Modulus of a Complex Number

The formula |z| = (x2 + y2) gives the modulus of a complex number z = x + iy, represented by |z|, where x is the real component & y seems to be the imaginary part of the complex number z. The conjugate of z can also be used to compute the modulus of a complex number z. Since 

Graphing the Modulus of a Complex Number

The distance between the complex number’s coordinates as well as the centre on the t complex plane is termed the modulus of the complex number when it is shown on a graph. A complex number’s modulus is the distance between two complex numbers. Presented as a point on the argand plane (a, b). This distance is measured as r = (a2 + b2) and is a linear distance from the centre (0, 0) to the point (a, b).

Furthermore, the Pythagoras theorem can be used to determine the modulus of a complex number. The hypotenuse represents the modulus, the real component is the basis, and the imaginary part seems to be the altitude of the right-angled triangles.

Modulus of Complex Number Properties

Some of the features of a complex number are listed below. When z and w are both complex numbers, we get;

  • The modulus of the complex numbers z and -z is the same, i.e., |z| = |-z|.
  • A complex number’s modulus is 0 if and only if the answer is zero, that is, |z| = 0 if z=0
  • The modulus of a complex number’s product equals the modulus of the product of complex numbers, i.e., |z. w| = |z|. |w|
  • |z/w| is equal to |z|/|w|. A quotient of two complex numbers’ modulus numbers is equivalent to a quotient of a modulus of the complex numbers.
  • The modulus of a complex number’s nth power is equal to the modulus of the complex number’s nth power, i.e., |zn| = |z|n

Important Notes on Complex Number Modulus

  • The distance between a complex number and the origin (0, 0) is the modulus of a complex number. Expressed as a point on the argand plane (a, b).
  • A complex number’s modulus is 0; however, if the complex number is 0.
  • The amplitude (or length) of the vector encoding a + bi is the same as the modulus of a complex number a + bi.
  • The square root of a sum of squares of the real and imaginary parts of a complex number seems to be the modulus of the complex number.

Conclusion

The conjugate of a complex number reflects a complex number around the real axis in the argand plane. Meanwhile, the modulus of a complex number is the distance of a complex number from the origin in the argand plane. Numbers of form a + bi, where I =, and a and b are real numbers, are complex numbers. They’re employed in a wide range of calculations and scenarios. Complex numbers are useful for our needs because they allow us to compute imaginary roots and obtain the square root of a negative number. Complex numbers come in extremely handy in a wide range of scenarios. They can be found in nearly every discipline of mathematics.

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Frequently asked questions

Get answers to the most common queries related to the UPSC Examination Preparation.

What is the best way to express the modulus of a complex number?

Ans. The distance between the origin and the point of a complex number is called its modulus on the argand plane, re...Read full

Is a complex number's modulus always positive?

Ans. Yes, a complex number’s modulus always seems positive or equal to 0.

In a complex number, what is the modulus of z?

Ans. Complex numbers are numbers of the pattern z = x + iy, where x denotes the real component of the complex number...Read full

When a complex number's imaginary part is zero, it reduces to?

Ans. If b = 0 in z = a + ib (a, b R), then z = (a, 0) = a + 0 I = a (which is a real component), implying that the c...Read full