(Examples)
(Definition)
 
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== Definition ==
 
== Definition ==
* the complex numbers are combinations of both real parts and imaginary parts, denoted ''i''.
+
* The complex numbers are combinations of both real parts and imaginary parts, denoted ''i''.
 
* These can be written ''a+bi'', where a and b are real numbers.
 
* These can be written ''a+bi'', where a and b are real numbers.
  
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== Examples ==
 
== Examples ==
*<math>|1+2j| = \sqrt{1^2+2^2}</math>
+
*<math>|1+2j| = \sqrt{1^2+2^2} = \sqrt{5}</math>
*<math>|1+2j| = \sqrt{5} </math> <br>
+
 
*<math>|1-2j| = \sqrt{1^2+(-2)^2} =\sqrt{5}</math>
 
*<math>|1-2j| = \sqrt{1^2+(-2)^2} =\sqrt{5}</math>
*<math>e^{j60} = cos 60 +jsin 60</math>
+
*<math>e^{j60} = cos 60 + jsin 60</math>
 +
*<math>e^{-j60} = cos 60 - jsin 60</math>

Latest revision as of 17:59, 2 September 2008

Definition

  • The complex numbers are combinations of both real parts and imaginary parts, denoted i.
  • These can be written a+bi, where a and b are real numbers.

Some Operations

  • $ j^2 = -1 $
  • $ |a+bj| =\sqrt{a^2+b^2} $
  • $ |z| = |\overline z| $ , where z is complex number
  • Euler Equation : $ e^{aj} = cos a + isin a $

Examples

  • $ |1+2j| = \sqrt{1^2+2^2} = \sqrt{5} $
  • $ |1-2j| = \sqrt{1^2+(-2)^2} =\sqrt{5} $
  • $ e^{j60} = cos 60 + jsin 60 $
  • $ e^{-j60} = cos 60 - jsin 60 $

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