View source for E infinity and P infinity for DT signal - Jamis Martin (jfmartin) - Rhea

<math>x\left[n\right]= \sqrt{n}*u \left [ n \right ] </math><br>

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<math>E_{\infty}=\sum_{n=-\infty}^{\infty} \left | x \left[  n \right ]  \right | ^2 =  \lim_{N \rightarrow \infty } \sum_{n=-N}^{N} \left | x \left[  n \right ]  \right | ^2</math><br>
<math>E_{\infty}=\sum_{n=-\infty}^{\infty} \left | \sqrt{n}*u \left [ n \right ]   \right | ^2</math><br>
<math>E_{\infty}=\underbrace{\sum_{n=-\infty}^{-1} \left | \sqrt{n}*u \left [ n \right ]  \right | ^2}_{0} + \sum_{n=0}^{\infty} \left | \sqrt{n}*u \left [ n \right ]   \right | ^2</math><br>
<math>E_{\infty}=\sum_{n=0}^{\infty} n = \lim_{N \rightarrow \infty } \sum_{n=0}^{N} n</math><br>
<math>E_{\infty}= \lim_{N \rightarrow \infty }   \frac{N \left ( N+1 \right ) }{2} =\infty</math><br>

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<math>P_{\infty}=\lim_{N \rightarrow \infty } \frac{1}{2N + 1} \sum_{n=-N}^{N} \left | x \left[  n \right ]  \right | ^2</math><br>
<math>P_{\infty}=\lim_{N \rightarrow \infty } \frac{1}{2N + 1} \sum_{n=-N}^{N} \left | \sqrt{n}*u \left [ n \right ]  \right | ^2</math><br>
<math>P_{\infty}=\lim_{N \rightarrow \infty } \frac{1}{2N + 1} \sum_{n=0}^{N} n</math><br>
<math>P_{\infty}=\lim_{N \rightarrow \infty } \frac{1}{2N + 1} \frac{N \left ( N+1 \right ) }{2}=\infty</math><br>