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IMAGINARY PART

Imaginary Part

Definition Of Imaginary Part

If z = x + iy is a complex number, then y is called the Imaginary Part of the complex number z.

More About Imaginary Part

The imaginary part of a complex conjugate is opposite to the sign of the imaginary part of that complex number.
If z is a complex number and zÌ… is its conjugate complex, then the imaginary part of z is given by Imaginary Part.

Video Examples: Finding Real and Imaginary Parts
 

Example of Imaginary Part

The imaginary part of a complex number 3 - 4i is - 4.

Solved Example on Imaginary Part

Ques: Choose the imaginary part of the complex number 7 + 8i. 

Choices:

A. 8i
B. - 7
C. 7
D. 8
Correct Answer: D

Solution:

Step 1: The imaginary part of the complex number 7 + 8i is 8.
[The imaginary part of the complex number a + ib is b.]

Quick Summary

  • The imaginary part of a complex number z = x + iy is y.
  • It's the coefficient of the imaginary unit 'i'.
  • The imaginary part is a real number.
\[ z = x + iy; Im(z) = y \]

🍎 Teacher Insights

Emphasize that the imaginary part is the coefficient of 'i' and is a real number. Use visual aids like the complex plane to illustrate the real and imaginary parts.

🎓 Prerequisites

  • Real Numbers
  • Basic Algebra
  • Complex Numbers Basics

Check Your Knowledge

Q1: What is the imaginary part of the complex number 2 + 5i?

Q2: What is the imaginary part of the complex number -7 - i?

Q3: What is the imaginary part of the complex number 9?

Frequently Asked Questions

Q: What is the imaginary part of 5 - 3i?
A: The imaginary part is -3.

Q: Is the imaginary part an imaginary number?
A: No, the imaginary part is a real number.

Q: What is the imaginary part of a real number (e.g., 7)?
A: The imaginary part of a real number is 0.

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