# Linearity questions

Discussion in 'Homework Help' started by sukalpa mishra, Oct 1, 2013.

1. ### sukalpa mishra Thread Starter New Member

Oct 1, 2013
3
0
PLease share with me the answer to these kinds of question...and tell me a procedure to solve such kinds of questions
given a time invariant system
x1(n)={1,0,2}=====>y1(n)={0,1,2}
x2(n)={0,0,3}=====>y2(n)={0,1,0,2}
x3(n)={0,0,0,1}=====>y3(n)={1,2,1}
with the provided information question asked is whether the given system is linear or noT?
i have tried finding out the z tranform of the input and output and find the z tranform of the output to find the system transfer function but its coming different for all the inputs...is it a confirmation that its non linear or not?can anybody explain?

Last edited: Oct 1, 2013
2. ### WBahn Moderator

Mar 31, 2012
18,085
4,917
I can't make heads or tails of your information. You have a sequence of three leading to a sequence of three, a sequence of three leading to a sequence of four, and a sequence of four leading to a sequence of three.

3. ### wayneh Expert

Sep 9, 2010
12,378
3,231
Haha, so glad it wasn't just me. That notation looked like gibberish to me.

4. ### sukalpa mishra Thread Starter New Member

Oct 1, 2013
3
0
i m sorry if i was not discriptive enough before....what i meant was that x1(n) signal ws passed through a system which displayed the output as y1(n) and same goes for the x2(n) and x3(n)....i hooe i m being clear this time...i m not making this question up.......it was asked if we can find out whether the system in non linear.....or linear!?

5. ### WBahn Moderator

Mar 31, 2012
18,085
4,917
I have a hard time seeing how it could be linear if the very number of samples in the output sequence isn't the same even when you have the same number of samples in the input sequence.

6. ### sukalpa mishra Thread Starter New Member

Oct 1, 2013
3
0
thanking for acknowledging that...but i wanted to know if there was a mathematical way of proving that this system is non linear .....

7. ### WBahn Moderator

Mar 31, 2012
18,085
4,917
Well, what is required, mathematically, for a system to be linear?