Time-Invariant and Time-Variant Systems 

How did my professor manage to tell this in 5 weeks of lectures and I still didn't get it, while I'm watching a 10 minute video about it and instantly grasp it. Great video man.

clear, eloquent, organized and straight to the point

Great explanation. Totally a great one that our college's lecturers cannot give.

2 min in: Great explanation, that was all I needed!

Your way of teaching is so much satisfying. You made me not get bored while listening. Thank you.

awesome teaching .... thank u sir... keep updating the channel u dont know how much we are benefited by your lecture videos

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TV System TIV System TV System

Thank you sir.... generally I have fear of signals subjects.....but because of these lectures it make me Soo comfortable

1. Time variant 2. Time invariant 3. Time variant because at first when input is passed from system we get y=cos(t)+x(t) and after passing from delayed to system we get y(t)=cos(t-to)=x(t-to). Second when input passed from delayed system we get x(t)=x(t-to) and after passing through system we get y(t)=cos(t)+x(t-to).so its not equal hence it TIME VARIANT .

1. TV 2. TIV 3.TV For anyone facing difficulty in solving the HW problems, finish the next lecture and you'll easily complete this problems.

1.TV 2.TIV 3.TV In 3rd problem, x(t) is input and cost is the term obtained from the system's output.

the transformation t->-s reveals, essentially that any function of (-t) will transform backwards in time with a time shift.

Keep it up! Honestly helped a lot.

I have about 20 hours until my first systems and signals exam. This explained it very well. Thank you.

1. TV x(sint - sint0) != x(sint - t0) 2. TIV x(t-t0+2) == x(t-t0+2) 3. TV cos(t-t0) - x(t-t0) != cost - x(t-t0)

Great explanation

sir, you presented the concept very clear!

Very clear explanation...thank you so much Sir

You are genius sir ! Thanks for making study easy :)

your work is excellent...!!! :)

Great explanation, thank you

@NesoAcademy its a very humble request please post answers of HW questions.

Really cool explanation very clear and catchy 🤩🤩

much useful video for student sir Thank you very much

amazing explanation sir

Thank you very much!

Neatly done sir...

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nice teaching sir

sir Did u r complete fouries series and transforms and laplce transforms in this course

Keep going. Reall nice

Earlier we studied that in time transformation the order ( shifting & scaling) doesn't matter. But isn't this property somehow contradict that point?

Super jiii .. it helped me a lot .....👌👌

it'd be very helpful to know the answers to the hw problems, because reading others answers is making confused.

absolute excellence

Thank you

Very nice explanation thank you (:

brilliant way of teaching - student from China

Bro ur great

Thanks!

Thank you so much ❤

Thank you sir

Thank u sir......

sir which model should v prefr on the basis of log likelihood value ..the time variant or time invariant ?pls answer

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U r amazing

My left ear really enjoyed that.

You are awsome sir

Pro tip: Watch at 1.25x speed for best results

Thanks

For all time. Always

First one is TV as time scaling is performed Second one is TIV as amplitude shifting is performed Third one is Tv

The videos are really helpful. But it would be complete if answers are given for verifying. Thanks!

Thank you...the best lecture for SAS ...

you are legend

then why we multiply 2 with t (naught) in the first step of number 1 example? 7:00

1) y(t)= x(sint) is time variant 2) y(t)=x(t+2) is time invariant 3) y(t)=cost+x(t) is variant the first and 3rd one is just depending on delay of time so time variant and the 2nd one has time with constant on both depending so its time invariant

sir plz for our confirmation plz also upload the answers of end problems

@Neso Acadmey ...please post the answers of the homework problems too!!!!!

in third homework question step 1) Will the cos(t) becomes cos(t-t0) when we perform delay by t0? The thing which is confusing me is, since the input signal is x(t) and cos(t) is a coefficient but at the same time cos(t) also depends on t. So, if we are giving the output signal in a system which performs delay on that signal, so should this system on perform delay on x(t) part of the output or should cos(t) also be included? Explanation will be appreciated.

U r awesome

TIV TIV TV is the final and true answer

Can anyone let me know the physical significance of Time variance? what does it represent?

Fan o u sir g..

Hello I want to ask, sorry if the question are little bit weird (because im still 12), but Delay by t。is mean what?, are basically mean t - t。?, and what is x(t) exactly?, what the paramaeter t do there?, are the value is actually the t and the x or y is just the name function?

Sir plz give the answers of the questions in the task

will delay apply to cost making it cos(t-to)?

Sir, when we delay the signal y(t) by time to, the new signal will be y(t+to). But why are you taking y(t-to) Sir? It will then become advancing the signal right?

all are time invariant. In 1st question, time shifting doesn't affect the result and in 3rd question, we only have to take x(t) because it is the input not cos(t).

Hello, could you explain please why the delay is substracted but not added?

How do we get the answers

can anyone one explain me mathematically the 3 question i.e, how y(t³) = x(t) is a TV system. Please mail me the picture of the solved problem. Thanks in advance

Home work questions Q1,2 are Time invarient & Q3 is Time invarient

please upload the answers of home work problems

Please someone can write the conclusion i'm studing in frensh but i don't make diffrence between the TIV and TV i really need them i'll pass my exam on this week so please help me

1.TV 2. TIV 3.TIV

how 1st one is Time variant

thank you dear for your video and learn this to we poeple. but i have question about : X(2t) I ask about your answer: that write this: x(2t-2t0) please describe for me at here about my question. Thank you dear teacher

How 3rd one is time variant pls someone tell

1,3 tv 2 tiv

First I found 1. to be TIV but further reasoning results in 1. being TV: In step #1 provide the delay t0 to the output y(t), giving y(t-t0). As y(t) is equal to x.sin(t), t is replaced by t-t0, giving y(t-t0) = x.sin(t-t0) = x[sin(t).cos(t0)-cos(t).sin(t0)]. In step 2, instead of providing the delay t0 to the output it is provided to the input x(t), giving x(t-t0). This is fed as input to the system which has the characteristic of performing the time scaling operation. The operation is taking the sinus of the time which is then multiplied by x. The time scaling operation is only performed on the time t itself, not on the constant t0. The resulting output of the system, therefore, is x.sin(t) - t0. This result is unequal to the result of step 1 above. Therewith 1. is TV. Correct me if I'm wrong. Thnx.

Guys tell me if you are getting some other answer to the H.W Qs. 1) Time Variant 2) Time Invariant 3) Time Variant

1:TV 2.TIV 3.TV

1.TV 2. TIV 3 TV

1- TV 2- TIV 3- TIV

TV TIV TV Bencho.......kal exam hai bachaliya sir aapne😉

How to do y(t)=x(-t)??

second example should be time variant i suppose. Because after delay in output the result should be 2(t-t0)x(t-t0)

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Neso, like the right fucking answer instead of the compliments JFC

if it's delayed by t0 why is it y(t-t0) not y(t+t0)??

❤️

1. TV 2. TIV 3. TV please tell whether I have done it correct or not.

Sir answers bta dijiye plz

Hi, in the first case, after going through the system the output y(t)= x(2t). Now if we provide a delay wouldn’t it be x(2t-to)? Similarly, in the second case the delayed input is x(t-to), and when this input is given to the system, wouldn’t it scale the whole parameter of the input and become x(2(t-to))? System is variant either way, but just for the clarification of the concept...

1)TV 2)TIV 3)TIV

Why do we denote delay as negative? For eg if a system is taking 5 s and I give a delay of 5s...shouldnt that be 10s....so why are we subtracting... It might be silly but please help

1. TV 2. T.IV 3. TV