Why does this one guy literally know EVERYTHING

@SoWe1

4 жыл бұрын

wouldn't ask him about pottery, pretty sure

@kerr1221

3 жыл бұрын

@@SoWe1 He's an engineer, so he actually probably could tell you a bit about pottery.

@SoWe1

3 жыл бұрын

@@kerr1221 you're not particularly skilled in any manufacturing field yourself, are you?

@kerr1221

3 жыл бұрын

@@SoWe1 I was a machinist for 10 years, so you could say I am. In school for EE now. Depending on where someone goes with their courses, learning about pottery and ceramics at some point is a possibility. We talked about them in my strength of materials class. Edit: At least in my program, engineers are exposed to a fair amount of hands on/manufacturing. Ofc that doesn't make them as good as people who do it for a job, but they aren't clueless.

@dalilpebble

3 жыл бұрын

@@kerr1221 r/iamverysmart

fucking support this channel everyone i hope in 2050 this guy will be recognized by MORE people and he makes it into history books and he becomes a fucking legacy.. not only sal.. but the etire khan acad team..

@irinakhlebanova7249

6 ай бұрын

Salman Khan

@dangerouslykeety

Ай бұрын

Totally 100% agree

I understand you much easier than my Russian native diff eq professor haha!

Khan Academy savior of all exams!

In beams problem we can apply this call separable differential equations , and I have come across with hinged beam ,where moment is zero at the hinge, and also x=L, so (L,0) is a coordinate point, initial condition , given information to find a particular solution ( M=Mx) moment function to a higher degree order differential equation which it only takes place within a member and linked with constrain of the structure, the use of principle of superposition will help us to analyse redundant forces by setting derivative forms.I would like to share my experience....any emai?

He has is own way of making people understand within minutes 🥺 thank you for being the best tutor

@user-ut4zh3pw7l

5 ай бұрын

sweet 🥺

Nice job good learning system help all out thank u

thank you for this sir!

Great video, thank you!

Thank you for your "advice".

Awesome, thanks!

Thank you for this video!

Why can't you cross multiply ?

Thank you very much sir , very clear and helpful, please please I need to know the software that you are working with please.

How can you multiply by dx? dx isn’t a number, it’s just a notational convenience for small changes (eg over a small amount of time). Can you explain that logic?

@mokkes7340

2 жыл бұрын

I know that I'm a little late... but remember that (dy/dx) represents a infinitimally small change of y over x, or the slope of a curve. So from a physical perspective, you can rearrange the formula to say that for every change in y (dy) it is equal to a change in x (dx). Hence why the transformation is very useful to describe physical phenomina.

thank you!

Hello i'm from Indonesia.. I see this because of the work of the lecturer. but I don't understand because I'm not very good at English. Thankyou❤️

@adipamungkasofficial

4 жыл бұрын

Mee too

2:34 "Little more space" lol

@zayedacademy988

6 жыл бұрын

watch our videos ,we are recreating his videos in a great way

thank you khan academy

sir which software are you using for these videos????

Looks simple enough!

very good

Awesome m8

i think its general solution, coz particular solution wouldn't have an independent variable that would vary each time it would have been constant!! If i got it wrong plz tell me what's the difference between particular solution and general solution ??

awesome

How do you get exponent of negative x square exponents in math?

@adampowell576

2 жыл бұрын

It was in the denominator and he brought it up to the numerator making the exponent negative.

In the first example, are we going to do integration by parts in -xe^-x^2 dx? I'm kinda confuse. Notice this one please. Thanks!

@SilverArro

4 жыл бұрын

dusky _gaming No. He does u substitution there, although he does it quickly and without going through the whole process since it’s easy enough to do in your head. He’s assuming you’re very familiar with integral calculus since it’s absolutely a prerequisite for a Differential Equations course.

@earonfazonela7912

4 жыл бұрын

No. It is exponential integration. Letting u= -x^2 therefore the du= -2x. That is why khan multiply it to 1/2.

@earonfazonela7912

4 жыл бұрын

No. It is exponential integration. Letting u= -x^2 so therefore the du= -2x.

can someone explain the integration part? where does he get the 1/2 to and all the other stuff from?

@ssyhrr9149

8 жыл бұрын

+Ryan Hugh He used u-substitution, by letting u= -x^2 (of exponential). So, he could use du/2 to substitute -x dx in the question. So basically that 1/2 u asked is coming from du/2. (1/2 S e^u du)

@AhmedMustafax

8 жыл бұрын

+Ryan Hugh His answer's right, I can't tell where he got the 1/2 from though.

@marxho

8 жыл бұрын

By sibstitution, u = -x^2, du = -2xdx, -xdx = du/2=(1/2)du.

@ZainKhan-xx6np

6 жыл бұрын

simple integration review the integration table. You will get the answer its v.Simple

Does someone know why y*dy integrated is equal to (1/2)y ^2 ? Im very confused because usually y integrated should be equal to (1/2) y ^2. but why is there the same solution with and without dy?

@carsonhenderson

3 жыл бұрын

when u take the integral the dy or dx just means you're taking the integral with respect to x or with respect to y so it goes away after the integral has been taken. If you were to see an integral of just dy, you assume you're taking the integral of 1 with respect to dy, so the integral of 1 is just y (+c). The integral of y with respect to dy is 1/2y^2 (+c) as you said.

@ascaniuspotterhead2484

3 жыл бұрын

Carson Henderson Thank you very much.

Hi! Do you think you could make a video on Euler's rule for differential equations? I don't fully understand it. Thanks!

@Dan-bg5fm

7 жыл бұрын

do you understand it now ?

@LoganBrewski

7 жыл бұрын

Wilfred I sure hope he does

@Dan-bg5fm

7 жыл бұрын

LoganBrewski lmao

@nickgiannakopoulos3171

3 жыл бұрын

@@Dan-bg5fm @LoganBrewski I hope he figured it out

@billybobandboshow

Жыл бұрын

@@nickgiannakopoulos3171 @Dan @LoganBrewski 13 years later....yes I understand it now lol

On the integration part you treated it like (e^-x)^2 and at the end you treated it like e^(-x^2) ... Isn't that a big mistake?

@theepicosityofpizza

4 жыл бұрын

He did no such thing. He treated it as e^-(x^2) in both.

Does anybody know a really good Calc I level explanation of why multiplying both sides by dx does not contradict the fact that dy/dx is not a fraction?

@I0lcatz

7 жыл бұрын

because it more or less is a fraction. at least it works exactly the same way, which is why its wrote like that.

At 5 min 56 seconds, couldn't you also multiply both sides by 2 to get rid of the 1/2 factor on each side and then plug in your point to solve for C. Your C would multiply by 2, but since it is an unknown constant that should not effect the answer. I did that and ended up with the answer of y= + - (e^(-x^2)+2)^0.5. My answer clearly is not as pretty, but I think it is also a correct answer.

@Electrologia

Жыл бұрын

yes of course you can do. it will not change the answer but will simplify it.

Hello can you solve the x*y*y'=x^2+1

@drofeng

2 жыл бұрын

yy' = y dy/dx = 1/2 d(y.y)/dx by the product rule Then 1/2 d(y^2)/dx = (x^2 + 1)/x Or d(y^2)/dx = 2x + 2/x Let u = y^2 du/dx = 2x + 2/x Separate the variables and solve, then substitute y^2 for u

I love you

how does he know the C value at 5:56 is +C (positive) and not -C(negative)? I understand that C2- C1, but there could be the case that C1 is larger than C2

@superroydude

7 жыл бұрын

Jomembawang He doesn't. C could be either but it being an arbitrary constant it doesn't matter. For example you can write -5 as +(-5) it doesn't matter ( you could have -C if you wanted).

@gregoryfenn1462

4 жыл бұрын

You could have also written C=(C1+C2)/2 which would be much neater

why can I do that? like, i thougt dy/dx was just a notation, not a real fraction

@drofeng

2 жыл бұрын

You can write in finite notation, multiply and then take the limit e.g. DeltaY / DeltaX = x^2 Then DeltaY = x^2 * DeltaX DeltaY = y(x + DeltaX) - y(x) dy = lim(DeltaX -> 0) y(x + DeltaX) - y(x) In the limit, dy = x^2 dx

I think there’s a mistake in the “intergration by parts”

why say differential equations,not derivative equation

God loves you and he wants to save you all

"Boat Sides" by y and dy

C = 1/2 though sir... I hope you notice.. Cuz you forgot the x must be equate with zero

@axelnils

7 ай бұрын

Absolutely not

i thought you couldnt treat dy/dx like a fraction.

@raullara6082

7 жыл бұрын

It's wrong but also not wrong to do so, but you can think of it as moving what side you will be differentiating. It works out. Depends on the context.

@Dan-bg5fm

7 жыл бұрын

?

@jacoblugtu8723

5 жыл бұрын

Raul Lara wait what do u mean wrong and not wrong

@Colonies_Dev

5 жыл бұрын

I guess the expression is true so you can use algebra?

Sal, there's a minor error in how you work out this problem. Once you separate the equation, you have -x * e^(--x^2)dx on the right. You don't show the steps of your u substitution, but you set u = --x^2. which means that du/dx = --2xdx In order to sub in, you have to multiply the right side by --2 inside the integral, and --1/2 outside of the integral. You forgot the negative sign on the 1/2, so your final solution is the wrong sign. I really appreciate your website, and I'm thankful that you do such a great job with your more complex topics. I'm taking a graduate physics course this fall, after not having done a math course in 15 years (I teach HS physics though), and I've used your site to refresh myself on trig, calc I, and differential equations. Your practice materials are great, especially the practice problems. Thank you so much for this awesome gift you have shared with us!

@muhammadrafay4743

4 жыл бұрын

i was thinking the same thanks for correcting it

@in4LifeTime

4 жыл бұрын

It’s actually correct, try using u = e^(-x^2), du = -2x e^(-x^2). He simply manipulates the equation by adding in a 1/2 to get the original expression which was -xe^(-x^2).

@satioOeinas

Жыл бұрын

@@in4LifeTime the answer should be +-sqrt(-e^-x^2+c), Sal forgot the - before e^x^2

I think we simply can't multiply with dx.

Hey first of all thanks for all the great videos. Secondly, please rethink your audio levels. With my computer's volume one tick above mute and the youtube volume slider at 1/3 of max, your video still needs to be turned down. When coming from just about any other video where both computer and player volume need to be on full to hear anything, starting one of your videos is physically painful.

please try using simple questions for your introductions.....not the one you used

@RickyPollo

4 жыл бұрын

As far as differential equations go, this is about as simple as it gets.

Lol and I have never studied this stuff but I already know what it is about

i dnt like how you started

kindly change your board color to white. Thanks

@zayedacademy988

6 жыл бұрын

watch our videos ,we are recreating his videos in a great way

I love you