(New page: == Introduction == * Complex numbers are typically represnted in the form <math>(a + bi)\!</math>, where <math>i=\sqrt{-1}\!</math> and <math>i^2=-1\!</math>. The variable <math>a\!</math...)
 
 
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=Basic Complex Number Operations  ([[Homework_1_ECE301Fall2008mboutin|HW1]], [[ECE301]], [[Main_Page_ECE301Fall2008mboutin|Fall 2008]])=
 
== Introduction ==
 
== Introduction ==
 
* Complex numbers are typically represnted in the form <math>(a + bi)\!</math>, where <math>i=\sqrt{-1}\!</math> and <math>i^2=-1\!</math>.  The variable <math>a\!</math> reprents the real part and the variable <math>b\!</math> represents the imaginary part.
 
* Complex numbers are typically represnted in the form <math>(a + bi)\!</math>, where <math>i=\sqrt{-1}\!</math> and <math>i^2=-1\!</math>.  The variable <math>a\!</math> reprents the real part and the variable <math>b\!</math> represents the imaginary part.
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* Multiplication of complex numbers follows the basic commutative and distributive laws.  Keep in mind <math>i^2=-1\!</math>.   
 
* Multiplication of complex numbers follows the basic commutative and distributive laws.  Keep in mind <math>i^2=-1\!</math>.   
 
<math>(a+bi)(c+di)=a(c+di)+(bi)(c+di)=ac+adi+bci+bdi^2=(ac-bd)+(ad+bc)i\!</math>
 
<math>(a+bi)(c+di)=a(c+di)+(bi)(c+di)=ac+adi+bci+bdi^2=(ac-bd)+(ad+bc)i\!</math>
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== Dividing Complex Numbers  ==
 
== Dividing Complex Numbers  ==
 
* Division of complex numbers is usually done by multiplying the numerator and denominator by a complex number that will get rid of the <math>i\!</math> in the denominator:
 
* Division of complex numbers is usually done by multiplying the numerator and denominator by a complex number that will get rid of the <math>i\!</math> in the denominator:
 
<math>(a+bi)/(c+di)=((a+bi)(c-di))/((c+di)(c-di))=((ac+bd)+(bc-ad)i)/(c^2+d^2)\!</math>
 
<math>(a+bi)/(c+di)=((a+bi)(c-di))/((c+di)(c-di))=((ac+bd)+(bc-ad)i)/(c^2+d^2)\!</math>
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[[Main_Page_ECE301Fall2008mboutin|Back to ECE301 Fall 2008 Prof. Boutin]]
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[[ECE301|Back to ECE301]]
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Visit the [[ComplexNumberFormulas|"Complex Number Identities and Formulas" page]]

Latest revision as of 17:49, 4 January 2011

Basic Complex Number Operations (HW1, ECE301, Fall 2008)

Introduction

  • Complex numbers are typically represnted in the form $ (a + bi)\! $, where $ i=\sqrt{-1}\! $ and $ i^2=-1\! $. The variable $ a\! $ reprents the real part and the variable $ b\! $ represents the imaginary part.


Adding Complex Numbers

  • Addition of two complex numbers is done by adding the real parts together and the imaginary parts together:

$ (a+bi)+(c+di)=(a+c)+(b+d)i\! $


Subtracting Complex Numbers

  • Subtraction of two complex numbers is done by subtracting the real parts and the imaginary parts seperately:

$ (a+bi)-(c+di)=(a-c)+(b-d)i\! $


Multiplying Complex Numbers

  • Multiplication of complex numbers follows the basic commutative and distributive laws. Keep in mind $ i^2=-1\! $.

$ (a+bi)(c+di)=a(c+di)+(bi)(c+di)=ac+adi+bci+bdi^2=(ac-bd)+(ad+bc)i\! $


Dividing Complex Numbers

  • Division of complex numbers is usually done by multiplying the numerator and denominator by a complex number that will get rid of the $ i\! $ in the denominator:

$ (a+bi)/(c+di)=((a+bi)(c-di))/((c+di)(c-di))=((ac+bd)+(bc-ad)i)/(c^2+d^2)\! $



Back to ECE301 Fall 2008 Prof. Boutin

Back to ECE301

Visit the "Complex Number Identities and Formulas" page

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