For each of the following discrete systems, determine whether they are ( Linear, Shift-Invarian, Causal, Memoryless, Stable)

EE351, Spring 2017, Zahid

Extra Credit #2

Due: Sunday, February 5, Midnight

Please read the following notes carefully:

1. Extra credit assignments will be assigned periodically throughout the

semester. The extra credits will be added to your midterm scores at

the end of the semester.

2. Extra Credits are individual efforts; they are not group projects. Any

indication of copying from each other will results in a grade of F. It is

not worth the embarrassment!

3. Extra Credits are OPTIONAL. You don't need to submit them if you

are confident that you will do well in class and you won't need the help

4. All submissions (detailed, I am not interested in answers only or in Yes

or No?) must be e-mailed to [email protected]. Your attachment must

be in a word/pdf/scanned file format. NO TEXT attachments and NO

hardcopy. You must include your full name on every page (not only in

the e-mail) of your solutions file and you MUST specify the following

in the subject field of your e-mail "EE350-Extra Credit-Set #2".

5. When assigned, extra credits will always be assigned on Thursday

night. They are due midnight the following Sunday). Your e-mail has to

indicate the time of submission. No late submissions are accepted no

matter what the reasons are.

6. Here is the first x-credit assignment. It is due Midnight, Feb 5. Good

Luck.

1. For each of the following discrete systems, determine whether they are

 Linear

 Shift-Invariant

 Causal

 Memoryless

 Stable

Clearly show your work.

a) y(n) = nx(n)

b) y(n) = x(2-n)

c) y(n) = x(n)u(n)

d) y(n) = x(n)x(n-1)

2. Find whether each of the following sequences is periodic or not. If

periodic what is the period, if not why not.

a. x(n) = ej7n/9

b. x(n) = cos(6n/9)

c. x(n) = sin (7n/9)