Chapter 1: Problem 48
Find the product of the given complex member and its conjugate. $$4+3 i$$
Short Answer
Expert verified
25
Step by step solution
01
Identify the given complex number
Given complex number is: \(4 + 3i\)
02
Find the conjugate of the complex number
The conjugate of a complex number \(a + bi\) is \(a - bi\). Hence, the conjugate of \(4 + 3i\) is \(4 - 3i\).
03
Set up the product of the complex number and its conjugate
To find the product, multiply the complex number by its conjugate: \((4 + 3i)(4 - 3i)\).
04
Apply the difference of squares formula
Use the identity \((a + b)(a - b) = a^2 - b^2\). Here, \(a = 4\) and \(b = 3i\) , so it becomes \((4)^2 - (3i)^2\).
05
Simplify the expression
Calculate \((4)^2 - (3i)^2\). This results in \(16 - 9i^2\). Since \(i^2 = -1\), it simplifies to \(16 - 9(-1)\).
06
Calculate the final result
Simplify \(16 + 9\) to get \(25\).
Unlock Step-by-Step Solutions & Ace Your Exams!
-
Full Textbook Solutions
Get detailed explanations and key concepts
-
Unlimited Al creation
Al flashcards, explanations, exams and more...
-
Ads-free access
To over 500 millions flashcards
-
Money-back guarantee
We refund you if you fail your exam.
Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Complex Conjugate
A complex conjugate is very useful in various calculations involving complex numbers. The complex conjugate of a number in the form of \(a + bi\) is \(a - bi\). Here, \(a\) and \(b\) are real numbers, while \(i\) is the imaginary unit. The conjugate essentially flips the sign of the imaginary part.
Why do this? The main reason is because multiplying a complex number by its conjugate eliminates the imaginary part. For example, if we have \(4 + 3i\) and multiply it by its conjugate \(4 - 3i\), the imaginary section disappears:
Why do this? The main reason is because multiplying a complex number by its conjugate eliminates the imaginary part. For example, if we have \(4 + 3i\) and multiply it by its conjugate \(4 - 3i\), the imaginary section disappears:
- Given complex number: \(4+3i\)
- Conjugate: \(4-3i\)
- Product: \((4+3i)(4-3i)\)
Difference of Squares
The difference of squares formula is a useful algebraic identity applied often in mathematics. It states that \( (a + b)(a - b) = a^2 - b^2 \). When dealing with complex numbers, this identity is especially handy when you multiply a number by its conjugate. For the complex number \(4+3i\):
- First term, \(a = 4\)
- Second term, \(b = 3i\)
- Applying the identity: \( (4+3i)(4-3i) = 4^2 - (3i)^2 \)
Imaginary Unit
The imaginary unit, represented by \(i\), is defined as the square root of -1. It plays a crucial role in expressing complex numbers. The powers of \(i\) repeat in a cycle:
- \(i^1 = i \)
- \(i^2 = -1 \)
- \(i^3 = -i \)
- \(i^4 = 1 \)