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= [[:Category:Problem solving|Practice Problem]] on Z-transform computation  =
[[Category:ECE438]]
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[[Category:ECE438Fall2013Boutin]]
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[[Category:problem solving]]
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[[Category:z-transform]]
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= [[:Category:Problem_solving|Practice Problem]] on Z-transform computation =
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Compute the compute the z-transform (including the ROC) of the following DT signal:  
Compute the compute the z-transform (including the ROC) of the following DT signal:
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<math>x[n]= n^2 \left( u[n+3]- u[n-1] \right)  </math>
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<math>x[n]= n^2 \left( u[n+3]- u[n-1] \right)  </math>  
  
 
(Write enough intermediate steps to fully justify your answer.)  
 
(Write enough intermediate steps to fully justify your answer.)  
 +
 
----
 
----
==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 ==
 +
 
 +
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===
 
Andrei Henrique Patriota Campos
 
  
<math> x[n] = n^2 (u[n+2]-u[n-1])</math>.
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=== Answer 1 ===
  
<math>X(z) = \sum_{n=-\infty}^{+\infty} x[n] z^{-n}</math>
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Andrei Henrique Patriota Campos
 
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<math>= \sum_{n=-3}^{0} n^2 z^{-n}</math> 
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<math>= 9 z^3 + 4 z^2 + z </math>
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<span class="texhtml">''x''[''n''] = ''n''<sup>2</sup>(''u''[''n'' + 2] − ''u''[''n'' − 1])</span>.
  
<math>= z^3 (9 + 4 z^{-1} + z^{-2}) </math>
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<math>X(z) = \sum_{n=-\infty}^{+\infty} x[n] z^{-n}</math>  
  
<math>=X(z) = (9 + 4 z^{-1} + z^{-2})/(z^{-3})</math>, for all z in complex plane.
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<math>= \sum_{n=-3}^{0} n^2 z^{-n}</math>  
  
===Answer 3===
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<span class="texhtml"> = 9''z''<sup>3</sup> + 4''z''<sup>2</sup> + ''z''</span>
Muhammad Syafeeq Safaruddin
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<math>x[n] = n^2(u[n+3]-u[n-1])</math>
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<span class="texhtml"> = ''z''<sup>3</sup>(9 + 4''z''<sup> − 1</sup> + ''z''<sup> − 2</sup>)</span>  
  
<math>x[n] = n^2(\delta(n+3)+\delta(n+2)+\delta(n+1)+\delta(n))</math>
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<span class="texhtml"> = ''X''(''z'') = (9 + 4''z''<sup> − 1</sup> + ''z''<sup> − 2</sup>) / (''z''<sup> − 3</sup>)</span>, for all z in complex plane.
  
<math>X(z) = \sum_{n=-\infty}^{+\infty} x[n] z^{-n}</math>
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=== Answer 3 ===
  
<math>X(z) = \sum_{n=-\infty}^{+\infty} n^2(\delta(n+3)+\delta(n+2)+\delta(n+1)+\delta(n)) z^{-n}</math>
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Muhammad Syafeeq Safaruddin
  
<math>X(z) = 9z^3+4z^2+z+1</math> for all z in complex plane
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<span class="texhtml">''x''[''n''] = ''n''<sup>2</sup>(''u''[''n'' + 3] − ''u''[''n'' − 1])</span>  
  
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<span class="texhtml">''x''[''n''] = ''n''<sup>2</sup>(δ(''n'' + 3) + δ(''n'' + 2) + δ(''n'' + 1) + δ(''n''))</span>
  
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<math>X(z) = \sum_{n=-\infty}^{+\infty} x[n] z^{-n}</math>
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<math>X(z) = \sum_{n=-\infty}^{+\infty} n^2(\delta(n+3)+\delta(n+2)+\delta(n+1)+\delta(n)) z^{-n}</math>
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<span class="texhtml">''X''(''z'') = 9''z''<sup>3</sup> + 4''z''<sup>2</sup> + ''z'' + 1</span> for all z in complex plane
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<br>
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=== Answer 3 ===
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Write it here.
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=== Answer 4 ===
  
===Answer 3===
 
 
Write it here.
 
Write it here.
===Answer 4===
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Write it here.
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=== Answer 5 ===
----
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[[2013_Fall_ECE_438_Boutin|Back to ECE438 Fall 2013 Prof. Boutin]]
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Tony Mlinarich
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 +
<math>X(z) = \sum_{n=\-infty}^{+\infty} x[n] z^{-n}</math>
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 +
<math>X(z) = n^2(\delta(n+3)+\delta(n+2)+\delta(n+1)+\delta(n)+\delta(n-1)) z^{-n}<\math>
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 +
<span class="texhtml">''X''(''z'') = 9''z''<sup>3</sup> + 4''z''<sup>2</sup> + ''z'' + ''1/z''<\span>
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 +
 
 +
[[2013 Fall ECE 438 Boutin|Back to ECE438 Fall 2013 Prof. Boutin]]
 +
 
 +
[[Category:ECE301]] [[Category:ECE438]] [[Category:ECE438Fall2013Boutin]] [[Category:Problem_solving]] [[Category:Z-transform]]

Revision as of 15:27, 12 September 2013

Practice Problem on Z-transform computation

Compute the compute the z-transform (including the ROC) of the following DT signal:

$ x[n]= n^2 \left( u[n+3]- u[n-1] \right) $

(Write enough intermediate steps to fully justify your answer.)


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

Andrei Henrique Patriota Campos

x[n] = n2(u[n + 2] − u[n − 1]).

$ X(z) = \sum_{n=-\infty}^{+\infty} x[n] z^{-n} $

$ = \sum_{n=-3}^{0} n^2 z^{-n} $

= 9z3 + 4z2 + z

= z3(9 + 4z − 1 + z − 2)

= X(z) = (9 + 4z − 1 + z − 2) / (z − 3), for all z in complex plane.

Answer 3

Muhammad Syafeeq Safaruddin

x[n] = n2(u[n + 3] − u[n − 1])

x[n] = n2(δ(n + 3) + δ(n + 2) + δ(n + 1) + δ(n))

$ X(z) = \sum_{n=-\infty}^{+\infty} x[n] z^{-n} $

$ X(z) = \sum_{n=-\infty}^{+\infty} n^2(\delta(n+3)+\delta(n+2)+\delta(n+1)+\delta(n)) z^{-n} $

X(z) = 9z3 + 4z2 + z + 1 for all z in complex plane


Answer 3

Write it here.

Answer 4

Write it here.

Answer 5

Tony Mlinarich

$ X(z) = \sum_{n=\-infty}^{+\infty} x[n] z^{-n} $

$ X(z) = n^2(\delta(n+3)+\delta(n+2)+\delta(n+1)+\delta(n)+\delta(n-1)) z^{-n}<\math> <span class="texhtml">''X''(''z'') = 9''z''<sup>3</sup> + 4''z''<sup>2</sup> + ''z'' + ''1/z''<\span> [[2013 Fall ECE 438 Boutin|Back to ECE438 Fall 2013 Prof. Boutin]] [[Category:ECE301]] [[Category:ECE438]] [[Category:ECE438Fall2013Boutin]] [[Category:Problem_solving]] [[Category:Z-transform]] $

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