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MODULUS OF A COMPLEX NUMBER

Modulus Of A Complex Number

Definition Of Modulus Of A Complex Number

Modulus of a Complex Number is the distance of the complex number from the origin in a complex plane. The modulus | Z | of a complex number Z = x + iy is given by Examples of   Modulus of a Complex Number.

More About Modulus of a Complex Number

Modulus is also called as Absolute Value.
Modulus of a Complex Number Z is also denoted as mod Z.
Modulus| Z | of a complex number Z is also given as Examples of   Modulus of a Complex Number , where Examples of   Modulus of a Complex Number is the conjugate complex of Z.

Examples of Modulus of a Complex Number

The modulus of complex number 3 + 4i is given as | 3 + 4i | = Examples of   Modulus of a Complex Number = Examples of   Modulus of a Complex Number = Examples of   Modulus of a Complex Number = 5.

Video Examples: Complex Numbers : finding the modulus and argument

Solved Example on Modulus of a Complex Number

Ques: Find the modulus of the complex number 18 + 24i.

Choices:

A. 18
B. 30
C. 24
D. 42
Correct Answer: B

Solution:

Step 1: Modulus of the complex number 18 + 24i is | 18 + 24i | = Examples of   Modulus of a Complex Number= 900 = 30.

Quick Summary

  • The modulus represents the absolute value or magnitude of the complex number.
  • It's the distance from the origin to the point representing the complex number in the complex plane.
  • It is always a non-negative real number.
\[ |Z| = \sqrt{x^2 + y^2} \]

🍎 Teacher Insights

Emphasize the geometric interpretation of the modulus as a distance. Use visual aids like the complex plane to illustrate the concept. Relate the modulus to the Pythagorean theorem.

🎓 Prerequisites

  • Real Numbers
  • Imaginary Numbers
  • Complex Plane
  • Pythagorean Theorem

Check Your Knowledge

Q1: What is the modulus of the complex number 3 + 4i?

Q2: What is the modulus of the complex number 18 + 24i?

Frequently Asked Questions

Q: What is the modulus of a complex number?
A: The modulus of a complex number is its distance from the origin in the complex plane. It is also known as the absolute value.

Q: How do you calculate the modulus of a complex number?
A: For a complex number z = x + iy, the modulus |z| is calculated as sqrt(x^2 + y^2).

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