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= [[:Category:Problem solving|Practice Problem]]: compute the zero-th order moment of a Gaussian random variable =
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= [[:Category:Problem_solving|Practice Problem]]: compute the zero-th order moment of a Gaussian random variable=
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A random variable X has the following probability density function:
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A random variable X has the following probability density function:  
  
 
<math>  
 
<math>  
 
f_X (x) = \frac{1}{\sqrt{2\pi} 3 } e^{\frac{-(x-3)^2}{18}} .
 
f_X (x) = \frac{1}{\sqrt{2\pi} 3 } e^{\frac{-(x-3)^2}{18}} .
</math>
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</math>  
  
Compute the moment of order one of that random variable. In other words, compute
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Compute the moment of order one of that random variable. In other words, compute  
  
<math>E \left( X^1 \right) .</math>
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<math>E \left( X^1 \right) .</math>  
  
 
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==Share your answers below==
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You will receive feedback from your instructor and TA directly on this page. Other students are welcome to comment/discuss/point out mistakes/ask questions too!
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== Share your answers below ==
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 +
You will receive feedback from your instructor and TA directly on this page. Other students are welcome to comment/discuss/point out mistakes/ask questions too!  
 +
 
 
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===Answer 1===
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Write it here.
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=== Answer 1 ===
===Answer 2===
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Write it here.
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The moment of n-th order moment is defined as: <math>E[X^{n}]=\int_{-\infty }^{\infty }x^{n}f_{X}(x)dx</math>
===Answer 3===
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Write it here.
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Therefore,
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<math>E[X^{1}]=\int_{-\infty }^{\infty }xf_{X}(x)dx=\frac{1}{3\sqrt{2\Pi }}\int_{-\infty }^{\infty }xe^{-\frac{(x-3)^{2}}{18}}dx=\frac{1}{3\sqrt{2\Pi }}9\sqrt{2\Pi }=3</math>
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=== Answer 2 ===
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Write it here.  
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=== Answer 3 ===
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Write it here.  
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[[2013_Spring_ECE_302_Boutin|Back to ECE302 Spring 2013 Prof. Boutin]]
 
  
[[ECE302|Back to ECE302]]
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[[2013 Spring ECE 302 Boutin|Back to ECE302 Spring 2013 Prof. Boutin]]
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[[ECE302|Back to ECE302]]
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[[Category:ECE302]] [[Category:ECE302Spring2013Boutin]] [[Category:Problem_solving]] [[Category:Continuous_random_variable]]

Revision as of 13:48, 23 March 2013

Practice Problem: compute the zero-th order moment of a Gaussian random variable


A random variable X has the following probability density function:

$ f_X (x) = \frac{1}{\sqrt{2\pi} 3 } e^{\frac{-(x-3)^2}{18}} . $

Compute the moment of order one of that random variable. In other words, compute

$ E \left( X^1 \right) . $


Share your answers below

You will receive feedback from your instructor and TA directly on this page. Other students are welcome to comment/discuss/point out mistakes/ask questions too!


Answer 1

The moment of n-th order moment is defined as: $ E[X^{n}]=\int_{-\infty }^{\infty }x^{n}f_{X}(x)dx $

Therefore,

$ E[X^{1}]=\int_{-\infty }^{\infty }xf_{X}(x)dx=\frac{1}{3\sqrt{2\Pi }}\int_{-\infty }^{\infty }xe^{-\frac{(x-3)^{2}}{18}}dx=\frac{1}{3\sqrt{2\Pi }}9\sqrt{2\Pi }=3 $

Answer 2

Write it here.

Answer 3

Write it here.


Back to ECE302 Spring 2013 Prof. Boutin

Back to ECE302

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