Laplace Transform 1

[dwilmer7]

"The notation is the "L" as in "Laverne and Shirley" (might be before your time...(actually i think it was re-runs in my time and ...well...anyway.... lol

[mehowee]

Very helpful, thanks

[toytoyGogie]

guys, why the antiderivative is -1/s not -1/st? because t == 1?

[huynh727]

@toytoyGogie because the integral is taken with respect to t. Therefore you only bring down the constant

[huynh727]

@huynh727 which, in this case, is s.

[LuLKurenai]

my exam 2morow, hope i can get it. thanks

[wussup331]

this video and your tutorial on convolution has got me through my signals and systems coursework! Thanks!

[dojOdRiFTeR]

in kahn we trust 

[RainbowDashXSyndrome]

"This is a significant moment in your life. You've been just exposed to your first Laplace Transform" It sounds like we lost our calculus virginity.

[amoresassybad]

u just saved me from stress!

[roniepao]

if you put graduated in Youtube University in your resume, youll get a job immediately.

[Gauss156]

"e ^ (STD)!!!!!!" Run away!!!

[antonio12554]

thank you with your explanation is been very helpfull on my studies.

[Jollyware11]

My head = mashed

[TheFlam3head]

I WALKED OUT OF MY CLASS WHEN I FOUND OUT WE WERE GUNNA COVER LAPLACE TRANSFORMS CUZ I KNEW IT WAS ON KHANACADEMY AND WELL WORTH IT! THK YOU!!!

[jochellefortune]

thanks a million

[pepteamsergi09]

Do you have any improper Fractions Videos yet????

[MingyaZarda]

The Mighty Khan, thank you (infinity) for sharing your knowledge of mathematics. I desire very strongly to understand this material before I depart this life (may need additional life's). Please keep up your very excellent work!

[curiosityuniversal]

Why would anyone dislike this! You're so amazing Khan!

Your explanation is very simple, slow, and easily understood!

Thanks for sharing!!!

[subzerofication]

hundreds of thousand people can understand maths better because of you....thanks.

[shiven10]

I needed this - got introduced to it at uni, but the lecturer can't explain whats going on.

Thanks Khan!

[Kucho29]

Khan taught maths to Chuck Norris!!

[89rafa]

@Kucho29 Ya. Thats true!

[eksman187]

Khan, we need some Fourier stuff !!

[muzik123beat]

Did you know a college which is called "Youtube College"??

[087bird]

My hero

[haoxag]

i can only watching this and take the exame to get a A. very easy understanding video..........

[sharawesley]

sounds like paul sheer!!!!!

[Cruth8987]

Dear Mr. Khan,

If you can read this, I truly wish you the best !

I cannot thank you enough for your videos, you are such a gift to the world !



[Dsunder1]

'use some of this real estate' lol



[Nojerome]

@metui1 I was in the middle of writing a comment on why anyone would dislike this when I saw your comment, and you are spot on sir.

[Jdiddy1792]

Well my professor was the first to introduce me to laplace transforms, but I didn't know wth he was talking about. Thanks for the videos! Come teach at my school!

[metui1]

the 8 dislikes on here are university lecturers pissed at you for doing their job

[Spyez]

Yeah a computer science would help seeing as that is what I'm majoring in at the moment.

[asfaqqq]

How come there aren't videos on computer science/engineering/dsp? I mean that's what khan majored in right? anyway nice vids, and I hope you could do some on fourier series and z transforms as well

[MouseKIller9000]

"So there you go this is a significant moment in your life, you have just been exposed to your first Laplace transform"

Laughed my ASS off!!!

Love the explanation, Thanks for your quality videos!! :)

~KhaliL~

[monkeyroadkill7]

duhFRENCHul equations

[Huseynelli]

Thank you for your time!

[tekerirem]

no me gusta este vídeo

[criznell]

@khanacademy ithink i luv you

[CostWar]

necesito sacar un muestreo, con valores discretos, pero para hacer una de fourier para después llevarlo al plano Z(Fourier) y compararlo con el plano S(Laplace).

ya tengo el procedimiento, pero pa confirmar, despues analizar de que rango a que rango puedo analizar, de que frecuencia el sistema presenta estabilidad y cuando me representa inestabilidad. y que hago cuando la frecuencia es demasiado alta para el muestreo en fourier, y de la ecuacion pueda concluir que el sistema presenta aliasing.

[CostWar]

@CostWar perdon, paso a paso, quiero saber como comparo el plano Z y el plano S, pero tengo problemas para decir la inestabilidad en un sistema, cuando la frecuencia es demaciado alta.

[CostWar]

como que cuando S> 0, esa mierda esta mal!!, ivas bien, pero la S, no la puedes quitar

[ludwin69]

vini, vidi, vici

saw this video, made and example, and got an A :D

wooooooooo!!

i love khanacademy!!!

[Lavabug]

Great little intro, definitely helps build up my confidence for my next mathematical methods course.

[Wodkabruder]

Dadda Daddy i hade my first Laplace Transform today.

No for real, this Video is great even for not native english speakers. ;-)

[thevidfather]

I've just finished the first term of my engineering course at Oxford and this was one of the topics covered (along with step/frequency response and transfer functions). Whilst our professor has provided us with decent notes, I always get more enjoyment out of watching your videos. I've been following your videos since high school and have always found your approach to teaching very personal and engaging, so I'm always looking out for relevant videos. Thanks, Sal! :D

[stikOplus63]

thanks!

[dgbennet]

thumb up if your from sussex uni, got the exam on laplace transform tomorrow and have just decided to check out youtube to find out what it means :p

[j9312]

you are very good at writing with a mouse on a computer

[goodbyelonglive44]

@j9312 he probably uses a pen..

[j9312]

@goodbyelonglive44 ur awesome. Thanks! OMG... no but in all seriousness I hadn't thought of that and you should be awarded a nobel prize. Im clearly not cut out for calculus.

[goodbyelonglive44]

@j9312 well he can use a pen over a touch pad screen, cant he?

[TheAfricanTiger101]

wow thanx, that really helped me 

[ratatabatata]

and what part of this im gonna use for engineering?

[naramanuel]

ur awesome

[moufpuncha]

Lavern and Shirley were so hot.

[lilhotwine99]

Nice videos. I wonder how many people downloaded it?

[ayaseele]

you are my hero. second to batman.

[ERUNAMExNIS]

I don't think I can thank you enough. I'm a second-year Mechanical Engineering student and this is great review for the DiffEq final.

[danilostebol]

thanks!

[ohjaysus28]

the e^-st integral was not done correctly... or at least not done using the e^-ax/a rule... this can be mis leading i feel

[goodgoodgoodful]

"This is a significant moment in your life. You've been just exposed to your first Laplace Transform". That's quite a sense of humor, Khan.. BTW thanks a lot :)

[tyfa3]

thnx so much, that was great !

[CanoeingQueen04]

You are completely saving me on my midterms. I'm just watching all of these!

[Valsheper1987]

Thank you very much! Laplace transform rocks in Viscoelasticity problems!:)

[LokiGalla]

I would like to tell you i appreciate your videos very much. They are a great help.

[amnesiai]

God i hated using these in my controls class

[BanderHM]

the way he says "infinity" is wonderful :)

[mamba52us]

thank you.

[vionorino]

could u do Fourier series! we like ur explanation!

[yoguely]

I've been having a super hard time in my calc II honors class. YOU SAVED MY LIFE!! THANKS!!!

[donbahadur]

thanx man ,,,,,,,thnx a lot ,,good job ,,i really appreciate ur job and help too

[donbahadur]

thanx man ,,,,,,,thnx a lot ,,good job ,,i really appreciate ur job and help too

[ares213]

I don't think you needed to cover improper integrals for this video. You may not have covered it prior to making this, but a student studying differential equations should already have learned it in calculus.

[speller88]

@ares213 that's what makes his videos so good.He makes sures he explains everything even an idiot would understand.Unlike the university professors who assume students know everything.lol

[veteran25]

A significant moment in your life. Lol. Thank you for that

[hypnotekk]

@veteran25 , haha. if my control teacher was as humourous as this guy i would have passed.

[dugbrewery]

Please do a Fourier series. thank you so much! i've learned a lot from you! :))

[mklvebu]

As always... Nice job!

[someonenice666]

Thank you man for this video it helped me.

T

H

A

N

K

S

[someonenice666]

Thank you man for this video it helped me.

[bryeinsteinmc2]

Damn you mathematicians and their limits. We physicists evaluate the integral exp(-st) dt from zero to infinity just by looking at it LOL

[sammyjny]

thanks for defining laplace transform. But I don't understand the meaning of the transformation. It says it transforms from "time domain" to "frequency domain" and I don't understand how it is doing that. If you could provide some theoretical analysis on it, that would be great. Secondly, do you have a video on inverse transformation?

[azmathmoosa]

well is there a video that tells HOW the s-domain is frequency domain. i mean how did laplace come to think of it. and is there a way of visualizing the transformation from time to frequency domain. in control system applications, lalplace transform is used heavily and i think understanding its fundamental nature will be very useful.

[alkalait]

Now is the time to do Fourier Series!!

[v2krules]

Simply amazing... one of the best set of tutor videos ever.. thank you

[buddydog1956]

It is significant to me! When I studied ODE's, my prof didn't teach us LaPlace Transforms (yea,  I know, a hellava guy)...now that I'm studying for the FE, I'm into them...and learning....yea me! thanks khanacademy!

[dwilmer7]

"an "L" like the "L" from Laverne and Shirley (might be before many of your times, but.. i grew up on that) (actually, i think it was all reruns when i was a kid")

Now whenever I do laplace transforms im always going to be thinking of laverne and shirley. lol

[VeXorian1337]

That's it?? I expected something worse, other than taking a limit of an integral...

[parthsna]

'This is a significant moment in you life', classic.

[nikanj]

I saw this concept listed in one of my university units so I looked it up on wikipedia. The article scared the pants off me so I looked it up on youtube and your video popped up. I'm not looking to learn to solve lapace transformations in great detail yet but this video makes it seem a whole lot less daunting.

[Ritzoid]

In complete awe.

[opjjuly]

hahaha..indeed this is a significant moment in your life!!! nice work work. but can u please do the fourier series?

[kinesisfilms]

i should be paying you to teach me instead of the hocus pocus i have right now!

thank you so much for the free education this is awesome!!!

[idiotlo]

love all your math videos man, it really helps

[immortalsae]

im 18 and still confused wether i should take this course or not 'cause im afraid i'll choose the wrong course.......... help me ;((

[ollienewth]

@immortalsae well, i have been doing engineering for about a year, and this is now just making sense to me - if you do this course, youtube will save your life with understanding all this!

[vickiormindyb]

I had no idea until yesterday that Laplace was the name of an actual Mathematician. I can't remember his first name.

My friend's husband, Alex, told me Laplace was a person. Alex went to MIT too. I don't know if that's where he learned it, but I never heard of it and I did High School Math.

[bashubacha]

hey khanacademy thank u son much, its a great video, and very helpful

[htam0000]

It's a shame that I waste so much money on a college education that I could get for free on Youtube...

[sunsetpeach]

@htam0000

and probably a better one too.

[htam0000]

so true...unfortunately

[silencedfable]

@htam0000

Very true... college is a lot of professors that already know their shit but cant teach you. But they give you deadlines. No deadlines one trying to learn stuff on youtube!

Takes a strong will to teach ones self especially when theres so many subjects wah

[samrustan]

@htam0000 college has little to nothing to do with learning.

[hussainkhalid]

well said, that is why im not attending college im studying by khan academy and think well...;)

[Ayplus]

@htam0000 Well, we'll see how valuable your YouTube diploma is :)

[saufi0601]

@htam0000 its more of a shame that free youtube lessons are better understood than the ones in college.

[mengqi68]

@htam0000 I agree.

[aakashba]

@htam0000 well u cant show a youtube degree to a job interview can u :P

[Timdotz]

At 5.55, how does -st = 1, when t goes to 0?

[jmohr00]

-st does not equal 1, but e^(-st) = 1 because e^0 = 1

[Dilekz]

Wow great lesson. Going to see more of your video's. Great thanks

[korrisha]

Man.. you got the best videos on here for mathematics. I am a maths major at UWI St Augustine Trinidad and these vids rock man been following you up for over a year now and I just want you to know how much we all appreciate your work....Keep the videos coming for the lectures in university are boring, monotonous and not as detailed and explained as your examples keep em coming wish I can meet you someday in person!!!!

[parthsna]

Could you do Fourier series/transform as well?

[secondhandsamson124]

@parthsna

yeah, and some Z transforms for signal processing?

[wholenote654456]

damn...and they all say that math is hard...

keep up the great job Sal.

[dakel7]

@wholenote654456 what are you talking about, this is so easy!

[azfanification]

Dear Sal,

Firstly many thanks for the amazing video!

could you please make a video on PARTIAL DIFFERENTIAL EQUATIONS please...(if you have time that is.)

thanks a lot for all you videos!

engineering year 1 student

[mauroprovatos]

since we integrate with respect to t, isnt

I(exp(-st) dt = -s exp(-st) ?

[AmiMerlin]

no, as he explains:

if you derive -1/s*exp(-st) you get exp(-st) if you derive -s*exp(-st) you get s²*exp(-st)

Hope this helps you understand

[MikeyFromDikey]

If you want to truly understand both Laplace and Fourier transforms, buy these two books: Signals by Lathi and Signals by Lyons.

[Sporky0000]

Using the method of series to solve a differential equation is skipped. Hehe, that stuff can get hard fast.

[hakireh]

Why my Professor are not so clear as him??! She took 1:30 h and only made me feel so confuse.. and in only 8 min i can see it clearly!!!

[camgere]

Great Videos! I'm always struck by how uselful product integrals are for engineering. Product integrals multiply and sum. Graphing each product is interesting. If you look at the integrals for cross correlation (similarity of funcions), convolution (time domain response) and Laplace and Fourier transform (time and frequency domain conversion) they are quite similar. e^-st has 0 DC average and from eulors formula is just -(cos(wt) +isin(wt))

[mumbles005]

your work is appreciated (Chemical Engineering UCLA, Los Angeles Ca)

[ashleeisa]

Haven't been to class in weeks, exam tomorrow, & full understanding of the material in just a few hours from watching these. Thank you!

[gematt7]

oh god finally i get what a laplace transform is :)... our maths guy is russian dude and has a voice that makes you wish you were dead

[SuperDownstairs]

wow, i think i might be in your class, is the dudes name Snopce?

[gematt7]

well theres plenty of russian lecturers :P... my dudes names sergey frolov

[crashonthehumble]

GOD bless you, keep on doing good, this world needs it.

[tamanduap]

Thanks from Chemical Engineering of Federal University of Minas Gerais (Brazil)

[choocooks]

thanks you so much saved me

[presidentemargarita]

Thanks a lot (Mechanical Engineering at The University of Texas at Austin)

[Indianmalujl]

@presidentemargarita UT Arlington Mechanical and Aero > UT Austin mech and aero.

[Michkuty]

wow, thanks alot man

[hector0282]

I'm a Mechaical Engineer, I remember taking the "Transformadas de LaPlace"........excellent memories from not long ago!.

[AlfonsoVolkova]

Thanks bro.. greetings from Mexico

[20053633]

Thanks from City University London : )

[erAshwanisoni]

good work Mr khan i hope i can have the same passion with which you teach

[nuur60]

tank u v.much man

[ouzairhafeez]

THANKS a lot man, God bless u!!!!!

From Pakistan.

[sameerk88]

ouzair, i am also from Pakistan!

this helps a lot.

[annie14411]

Hi does anyone know if he has posted anything on the fourier transform and partial differentiation,

thankyou

[oxvaldus]

this's very useful!!

Thanks from chile

[Khan98315]

Thankyou so much. Very interesting, funny, and informational.

[PhasmatisApparatus]

I find myself watching these videos weeks before I'll actually encounter the same material in class. :D

[bernardengks]

I owe you so much... from Malaysia....

[TheNishido]

Seriously... the only reason doing well in my degree is pretty much down to you, man! I owe you big time (if I ever stop being a penniless student I'll be sure to donate!).

[dravidr007]

thanks alot from imperial

[hebsh]

wow...nearly 14 hours leftto the test and i finally UNDERSTOOD WHAT THAT IS!!!!

thanks from germany:)

[ramjam19]

Thank you so much... you have no idea how much ppl u save everyday from suicide due to worthless teachers. GOD bless you!!!!!

[livvypants]

THANKYOU!!! you've saved me from much humiliation :)

[roverdome]

Great job! - thanks from Ireland

[croa76]

No entiendo mucho.., Todo por no saber inglés.

I do not undertstard so much. That is because i do not speak english.

[Krieghalter1]

Master of masters Mr Khan!!... why in my University times you wasn´t there (not youtube). You know? in youtube there are professors in spanish explainning math issues... but not match your level and way of explanation mr Khan! YOU REALLY WANT THAT PEOPLE UNDESRTAND EVERYTHING!! THAT´S GOLD!! AND THE BUNCH OF SUBJECTS YOU DOMAIN IS AWESOME... MY TOTAL REVERENCES MR KHAN!!!

Thanks and Greetings from Mexico city

[shaggydaplaya]

in electrical engineering:

s=jw , j being equivilant to i (an imaginary number) and we use j because i usually refers to current so we don't use it in wrong way.

1/s= integral of something

s=derivative of something ex: I=CdV/dt => I=sC

and then you can combine all s and 1/s and even cancel some s. This is of course for circuit design. So basically you do the laplace transform when you have complicated differential equations and you can simplify when some s terms cancel out then do reverse laplac

[bethel1n]

thanks for your interesting lecture. :)

[dasboot356]

Sal, go on with the good work! You are the best! Greetings from Germany!

[luthmhor]

Its interesting to find this stuff on youtube. I just finished first year engineering here in calgary and am taking a differential equations course this spring, my final is in a couple weeks.

This is better for me because the lectures go VERY FAST and i have to teach myself everything. Although as any engineering student knows that is common, ive had to teach myself pretty much all of the material in most of my courses :s.

[superbrando90]

hello!

I was wondering...when the DE is reduced into algebra and then its easier to solve, why does the transformation work in the first place as its defined?

[cdawgunit]

holay!!! he's soooooooooooo gud! - thanks from china

[superbrando90]

I agree its pretty gooooood

[Ba3dadBoy]

Can we fire our current lecturer and fly you over here instead?

[Sarahmarknz01]

Love it-thank you so much your a life saver-love engineering student NZ

[Ba3dadBoy]

MM2 aye. Hate that stuff. Good luck with the exam mate!

[amflaxx]

simplemente excelente... just perfect regards from Dominican Republic

[runnerlorena]

awethome :D

[OMGitsJOEE]

thaaaaaaank you! this vid helped a lot

[soulflyfgm]

amazing!! keep up the good work. Any fourier transformation lecture?