Question 3 : Signals :

How this is true? I am not getting it properly..

$$\large \color{green}{u[n] = \sum_{k \rightarrow - \infty}^{n} \delta[k]}$$

Question

Question 3 : Signals :

How this is true? I am not getting it properly..

$$\large \color{green}{u[n] = \sum_{k \rightarrow - \infty}^{n} \delta[k]}$$

anonymous · Answer

$u[n]$ is Unit Step Discrete signal

$\delta[k]$ is Unit Impulse or Sample Sequence..

anonymous · Answer

I think I have got this.. :)

anonymous · Answer

First case: For n < 0..

|dw:1409082614805:dw|

anonymous · Answer

Second Case: $n \ge 0$

|dw:1409082803607:dw|

anonymous · Answer

As :

It is equivalent to :

$ u[n] = \begin{cases} 1, && n \ge 0 \ 0, && n <0\end{cases}$

So:

$$\large \color{blue}{\sum_{k \rightarrow - \infty}^{n} \delta[k] = u[n]}$$