Gradient 1

[loveart161]

thank you very much for sharing this video

[myterribletube]

so you had i,j but you got 3d graph?

[MrMetacognition]

Weird how they form a right triangle.

[diegochilecruzado]

@MrMetacognition adding two perpendicular vectors does that..

[thecoast47]

@diegochilecruzado lol nice...

[muserocks69]

i fortgot to say thanks for the video

[muserocks69]

why have the partial derivatives the same magnitude? and shouldn't they be tangent to the function?

[EvilFatCat]

wow incredible explanation. thanks so much sal.

[MrDevin666]

I wonder why I'm looking at this when I'm only in Gr. 11 pre-cal IB lol

[PCGamerPortal]

@MrDevin666 cause unless you see it more formally it's really easy

[MrDevin666]

@PCGamerPortal I'm guessing you're in calculus or completed calculus?

[PCGamerPortal]

@MrDevin666 I'm finishing my third calculus course (out of 4)

[joshua50101]

@MrDevin666 because you are a narcisist who would want to draw attention to yourself, you would wanna get some guys tell you: hey, you are brilliant I can hardly understand this and you can.

[igotchubs4you]

@joshua50101 Dude, there is absolutely no way the kid understands a single thing that is going on in this video if he/she is only in pre-calculus; they haven't even learned what a derivative is let alone what it means in respect to multi-variable calculus or a gradient. 

[belostoky1]

someone knows where can i get a program similar to the one this lecturer has?

thank you

[seiscartas]

thank you. you have what it takes when it comes to explaining to people who dont understand easily, . keep it up!

[Bloodzee]

very clear explanation ... why dont colg profs watch your video to learn 'how to teach'..?

[a4b3c2d1e0f]

Amazing video indeed! Thank you, because I've been searching for a simple explanation of this and then found this :)

[MrTanookiMario]

Wow, thanks! I finally know what that darn upside-down delta operator is. The top-down view really helped me get what the gradient was getting at.

[tadm123]

did you created that graphing program?

[noobmaster31]

This was easy to understand. Can't wait to take this course next semester.

[CoOsMiiK]

IAM EINSTEIN

[CapitaineBleuten]

Really helpful, thanks. And your subtitles are very useful, allowing non-fluent english speakers to understand everything.

I'm not surprised you don't have any thumbs down !

[Sh4despawn]

wow that explains a whole lot, thanks!

[Password1andUsername]

the upside-down delta is a nabla ^^

[thatareally2]

adoraria que fosse em português! hahaha..



[viktorgoa]

is this the wolfram mathematica you plotted the graph?

[onaiderf]

I LOVE THIS KIND OF EXPLANATION! thank you so much

[V2PRC]

What is the software that you are using to plotting those 3D graphs, Sal?

[lokol456]

@V2PRC I think it is MAT lab, but I am not sure.

[royalconcrete1]

I'll just buy and play with what ya'll create. Keep creating and I'll keep buying.

[AmaymonF]

Thank you, dude . For all your nice videos and keep spreading the knowlegde :D

[fbf1451]

what program have u used to draw the graph?

[86shay86]

Is there a "Gredient 2" video....?

[naoufelabs1]

Thank you!

[sramanathan77]

wow... very nicely explained.. under which "course" have you put up this lecture?

[RecLuseGurL91]

wOw!! Love you guyzzzz , seriously, I totally get it :D

[lasarikabab]

YOU are the Best EVER!

[MultiThousands]

amazing!

thaaaaaank you khanacadem =)

شكراااااااااااااا

[antanare]

Exccelent!!!!!!!!! This video has helped me a lot!!! thank you. Muy buena explicación..ojalá y algunos aprendan a explicar así...supuestos "ingenieros"

[sponsoredwalk1]

Does anyone else see a hairy sack? :p

[fernq88]

OMG good explanation, greetings from Argentina =)

really USEFULL!!!!!

[100nassar]

PLEASE give the link for downloading this type of 3D derivative/surface plotting software.

I think you mentioned that you would give the link, but I guess you forgot--no wonder--so much going on !!

Thanks again,

--dale

[GlowStringTheory]

@100nassar in one of his later videos he drags the app far enough into the window that i could see the programs name. its called javaview. google magic! :D

[MrPlender]

I get how to partially differentiate and all that but I don't get the intuition behind these two gradient videos at all. The gradient is the steepness of a curve right? When we're finding the gradient with these multivariable functions what are we actually finding? Could someone explain to me as clearly and simply as possible?

[ncbookz]

@MrPlender he said the x y direction or i j components will give you the best direction to travel in that space so that z moves upward faster

[MarvelsofaLifetime]

When you took the Gradient of the equation at 0:45, why did you remove the (x,y) part of the equation. Is that just the notation used?

[rustydemon]

Amazing explanation!! Can finally visualize it!

Thank you :)

[maxbenjo]

Thank you, thank you, thank you!

[recplayandstop]

pErfect! thanks

[wetterhexe21]

perfect visualisation, thanks a lot!!

[Changer01]

So I find out the amount of z direction in any point in x,y plain just by multiplying the partial derivatives with the i and j vectors?

How do I actually find out the i and j vectors? Are they just the absolute values of the graph in this point?

[unsforlife]

but wait... when are you going to get into the Z traces? Hopefully in the next video...

[hsktoadftw]

i went through 97 videos in 1 day! fun learning with sal!

[negink89]

Perfect eplanation. Thank you so much; you saved me alot of confusion.

[mani19]

really good explanation

[fermixx]

so the gradient tells me the direction i should take to get as up (in the z axis) as possible moving as little as possible ?

so if im in the green side, i could go to the gray side and be upper in the z axis, but i would move way more, so the best ratio is to go to the green maximum?

thanks for sharing

[DISCARBURAT0R]

amazing !!! my lecturer sucks compare to your explanation.

[shaktiIIIgta]

damn straight !!!!! why i didnt find this earlier !!!! NIIIICE !!!!!!

thank you Khan academy

[autorancho]

SPASIBO!!!!!...that is thanks in russian.....

[DISCARBURAT0R]

@autorancho сорьки, я по ошибке на "poor cooment" нажал... я как раз таки "за" спасибо ;)

[autorancho]

VSE NORMALNO....BIVAET....

[quantomic1106]

youre awesome! thanks!

[eltotoX]

Very helpful! Calculus 3 is a pain! haha =)

[bigu]

very helpful, my theoretical physics class is going through this and I haven't even touched cal II yet so this is awesome!!!

[g1code]

you have heard a lot of thank yous and compliments , but hey Khan , please consider this :

you are giving the lot of viewers real MONEY , by not making them have to pay for tutors !! so you are mother Teressa !!

[Mrelevatorman]

Thank you for explaining this so well.

[BillFlann9]

DUDE!!!! You ROCK!!!

Where did you get the time to do all these vids?

I'm astounded!!

I'm also grateful, these vids are going to help me a lot. I'm starting Fields at NJIT this fall. I'm sure that I'm going to need a lot of excellent review of Calc III. Thank you very much!!!!

[abdulzuke]

si, yo creo que el acercarse a la ciencia de una forma amena, sencilla e intuitiva logra un mejor entendimiento, thank you, you have truly helped me

[sterm01]

hey does anyone know what the software is that he is using for the 3d graphs?

[andreimaster0]

I think it uses MAPLE for the 3d graphs

[luistr01]

exelente muchas gracias!!

[patriotSOS1]

thanks man it helped a lot

[zubairpnec]

well.. i have started to learn after watching this video.

[jmsoco]

I've been trying to understand gradients and directional derivatives all day and your video just taught me all those concepts in 10 minutes.

THANK YOU!

[avikbis]

thanx thanx thanx your videos helpd me a lot thanxkkkkkk

[upanddown2112]

I've never taken advanced math,

But I've always been facinated by it because of string theory, Hilbert's Space and all of that.

I've looked and looked for some way to interpret that complex language

AND THIS IS IT! THANKS SAL!

[saronghezai]

Amazing ! Why is Math not taught this way.Thank you again :)

[gambuzo]

As always, simply fantastic !!!

Your enthusiasm and simplicity are truly exemplary.

Once again thank you !

[ad2181]

excellent