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  @harmindersingh-rv5wb4 күн бұрын

  sorry bro u didn't help at all

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  @HebaKanfosa5 күн бұрын

  Thank you so much . Now i just have understood calculus.. a gain thank you till tomorrow morning.. Mohammed from Libya 🇱🇾🇱🇾

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  @doctari106110 күн бұрын

  Good explanation

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  @vynneve14 күн бұрын

  bad proof. that's wayyyy too "hand wavy". "dividing" by the infinitesimal dx to get the derivatives in there is just terrible form for a proof. technically does work (if you took some extra steps within that) but there is a much better way, just start with the derivative side, and apply the definition of derivative. (wont write various limits, should be implied) f'(x)/g'(x) = (f(x+h) - f(x))/(g(x+h) - g(x)) (the two denominator h cancel out) We can now evaluate the second terms at a (the lim to be calculated, h is also going to zero remember). But since we are assuming form of 0/0, f(a)=g(a)=0 so, = (f(x+h) - f(a))/(g(x+h) - g(a)) = f(x+h)/g(x+h) = we can now put 0 for h = lim x->a f(x)/g(x) as expected. Much easier imo, and objectively less messy of a proof.

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  @derekowens13 күн бұрын

  It is worth noting how rapidly these ideas took hold. The writings of Newton and Leibniz were adopted by the academic community almost in real time as they were developed. Newton was still alive and had not yet even moved to London when Bernoulli was writing about this rule, less than a decade after the publication of the Principia. And all of this was well over century before Cauchy began to formalize the theory of limits, and a full century and a half before Weierstrass. The point here is that a formal proof involving limits is actually unnecessary. History actually demonstrates this, as neither Newton nor Leibniz, nor anyone else at that time, used limits. Yet they *understood* these ideas and what these infinitesimal quantities represented. And if one understands this, then one understands when one can or cannot divide by dx. It was a conscious choice to approach the theorem this way, without the use of limits. The deliberate aim here is an *intuitive* proof, which I believe can make the concepts more clear and the understanding deeper. For another example, consider what Leibniz wrote to Wallace: "It is useful to consider quantities infinitely small such that when their ratio is sought, they may not be considered zero, but which are rejected as often as they occur with quantities incomparably greater. Thus if we have x + dx, then dx is rejected. Similarly we cannot have x dx and dx dx standing together as x dx is incomparably greater than dx dx. Hence if we are to differentiate uv, we write d(uv) = (u+dv)(v+dv) - uv = uv + vdu + udv + du dv - uv = v du + u dv" Where did the du dv go in this "proof"? If you understand the nature of these infinitesimal quantities, it makes complete sense. And then you can divide by dx on both sides and you have what we call the Product Rule.

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  @EvanLoper-tl9qj16 күн бұрын

  Does this apply to space? And light with distances so massive.

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  @derekowens14 күн бұрын

  Yes, it certainly does. You can think about the amount of light per square meter landing on earth and compare that the light per square meter landing on Mars, farther away. And on out to the more distant planets and beyond.

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  @yuminghu17 күн бұрын

  The angle of shadow keeps changing with the time during a day. How could he have synchronized the time to measure the angle when Syene was at noon?

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  @derekowens17 күн бұрын

  I believe that is because noon will be the moment at which the sun is at its highest in the sky, and therefore also the moment at which the shadow of a fixed object will at its shortest. He could mark the endpoint of the shadow once each minute or so. The shortest shadow is the one at noon.

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  @wrinkle178420 күн бұрын

  Here after more than 14 years and will take this knowledge with me till the day my cognitive abilities leave me .

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  @farmerbrown8421 күн бұрын

  There is one error here. When you get a "little device" to use your US made laptop in Europe, it does NOT convert the frequency and voltage back to 110V/50Hz. The little power adapter only changes the form of the plug, it changes NOTHING about the power voltage or frequency. The LAPTOP POWER supply will accept a wider range of power inputs - that's why it works. This is because the people that make laptops KNOW that the device is likely to be mobile. My laptop power supply says "100-240V 50-60Hz". Now, if you talk about an electric jug, or a toaster, then correct, the power difference will blow up your device because they are only made to take local (110V) power. Now, what about if you MOVE to Europe with all your household goods? Well, then you have a problem. It is possible to get a TRANSFORMER that will change the voltage of the 220V in Europe back to 110V for US appliances. They are big and heavy, especially for things that draw a lot of power like a toaster or electric kettle. Most people just buy new stuff, unless it's a special appliance. Note: the transformers do NOT change the frequency, so things like motors and clocks will run slower in Europe than the US (at 50/60ths of the speed). For a toaster, it can take 110V at 50Hz without issue. One last point. Many appliances I see sold in the US tend to only have 110V power supplies, whereas the equivalent model in Europe might support 100-240V. That's because they make 2 versions of the product: 1) a cheaper 110V only for the US and 2) more expensive 100-240V model for export. You have to check when travelling. Back in the day, much computer equipment shipped with either 100-120V OR 220-240V power supplies, or they had a switch to select the correct voltage. You had to be VERY careful outside North America if you ordered computers from the US not the blow the power supplies up after unpacking the box. Don't ask me how I know.

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  @derekowens21 күн бұрын

  Very helpful. Thank you. I also remember those power supplies with the switches on the back.

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  @Nivalian22 күн бұрын

  Thanks for the video. Is there uranium that has only a quarter uranium and three-quarters lead? Because if this exists, then it has been decaying for 9 billion years. The earth is only 4.5 billion.

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  @user-df1gr8vc3q25 күн бұрын

  This is rlly good

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  @Rittiuu25 күн бұрын

  Because v zero is from theta angle so vx will v cos thata I think you made mistake

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  @sinerntous6433Ай бұрын

  Knowledge is awesome.

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  @ColenzJoachimCameroАй бұрын

  is my method correct? since the wall is 20 meters high, i just solve for the maximum height of the projectile which is 12.33 meters and just by seeing the maximum height I can assume that it will not pass through the wall.

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  @derekowensАй бұрын

  Yes, that is valid, at least in *this* case. If the maximum height were higher than 20 meters, you would have to do a little more work. Specifically, you would need to determine if it is above 20m at the same moment it is at the horizontal position of the wall. Your approach shows a good intuition for solving this quickly. The more general solution is also valuable, though.

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  @jsacodes916Ай бұрын

  Man, thanks so much for this video. This was SUPER helpful.

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  @ruka2843Ай бұрын

  what if my question doesn’t give the initial velocity?

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  @derekowensАй бұрын

  In that case, you should be given some other information that will either allow you to find it, or will allow you to find something that will allow you to find it. In other words, from what you are given, you can typically find *something*, then something else, then something else, until you find the particular value you are aiming to find.

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  @tanveerhussain7965Ай бұрын

  Is it gives velocity or displacement?

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  @derekowensАй бұрын

  The slope of a position vs. time graph is the velocity. The displacement would be defined as the change in position, and we typically consider the change in position that occurs during some time interval. And that is what we are concerned with here: the change in position divided by the time interval is the slope of the position vs time graph, and that is the velocity.

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  @pawanyadav3399Ай бұрын

  Nice explanation 🙏🙏🙏🙏🙏🙏 sir...

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  @fernandogil745Ай бұрын

  So we can presume, the energy emitted at a higher level is bigger than the energy when absorbed. So different wavelengths?

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  @ShFTt2 ай бұрын

  Mitochondriac Manifesto brought me here. Very interesting and informative video, thank you!

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  @i-m-alien2 ай бұрын

  when iron heated so the size of atom increases...?

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  @derekowens2 ай бұрын

  It's not the size of the atom that increases but the *motion* of the atoms. At the atom level, heat is basically the vibration of the atoms. When the iron is heated, they shake back and forth more than when it is cool. And this extra movement requires more space, so the material has to expand.

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  @i-m-alien2 ай бұрын

  @@derekowens ...so the electron cloud size in increased...? means the track on which the electron is moving so the distance between tracks increases is it...?

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  @derekowens2 ай бұрын

  @@i-m-alien I don't think it's the electron cloud increasing in size as it is the atom as a whole moving around. Think about a bunch of people lined up sitting on a bench, sitting very close together, right against each other. If they start squirming, they will need more space. The people themselves don't get any bigger, but they require more room because of the additional motion. The squirming will tend to spread them out.

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  @i-m-alien2 ай бұрын

  @@derekowens ...ok means occilating the bangle kept on table , where the size of bangle will not change

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  @derekowens2 ай бұрын

  @@i-m-alien Yes, I believe that is the right idea. I'm just a high school physics teacher, though. If an actual physicist wants to read this and offer a more authoritative explanation that would be great.

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  @willpugh-calotte21992 ай бұрын

  What a great explanation! Sometimes a graphical demonstration like this, although not a rigorous proof to the academic standard, is sufficient for the student to "see" why some rule works. I had a similar problem when shown Descartes' Rule of Signs, but with no proof offered. When I tried to find a proof of Descartes' Rule, the offerings were too advanced for me. Eventually, I reasoned out a graphical justification for Descartes' Rule myself, and that was sufficient to put me "at peace" with the rule and move on.

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  @sharifahmed452 ай бұрын

  Could anyone kindly tell me what textbook the prof is using it? Thanks for the your prompt answer

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  @derekowens2 ай бұрын

  It's not a textbook, but rather a student workbook that is designed to go along with the videos. Students take notes and solve the problems in the workbook as they watch the lectures. This particular workbook is here: www.lulu.com/shop/derek-owens/calculus-semester-1-student-workbook/paperback/product-1qz4dyeq.html?q=Derek+Owens+Workbook&page=1&pageSize=4

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  @sharifahmed452 ай бұрын

  Thanks prof for your help, and kindly continue your contribution for the global student.

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  @rafsanjani78192 ай бұрын

  Holy crap, how can this video be 14 years old?

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  @maryamelharraq56432 ай бұрын

  شكندير هنا🙂

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  @friend6102 ай бұрын

  amazing explanation! tysm

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  @tindumon92242 ай бұрын

  Me seeing it after 14 years 😅

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  @Miguel_anitez2 ай бұрын

  Learned about this rule in my Ap Calc AB class a few months ago. I asked the teacher where it came from and why it works and she said to just use it and she didn’t fully know. Thanks for teaching me! I find calculus very fascinating to learn and it’s people like you who make the world a better place. Consider becoming a teacher, you are very skilled!

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  @fredrikrenstroem16612 ай бұрын

  Starting this video: "how the hell does l'hospital actually work?" Exiting: "yeah, that makes sense." Thanks🎉

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  @RonaldTani2 ай бұрын

  Thank you job well done ✅

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  @minakurtulan2 ай бұрын

  Youre the best . Thank you so much.

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  @jackychan46402 ай бұрын

  Thanks. I really need these solutions 😅

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  @user-rx6mc3vp9n2 ай бұрын

  Sin(-90)=?

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  @derekowens2 ай бұрын

  SIne of negative 90 degrees is -1. Negative 90 degrees puts you down at the very bottom of the unit circle, at the point (0, -1). And the sine of the angle is the y value.

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  @user-rx6mc3vp9n2 ай бұрын

  Good.

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  @jackychan46403 ай бұрын

  Thanks for your videos.

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  @nickayivor84323 ай бұрын

  👍

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  @shamstashin3 ай бұрын

  2024 Anyone?

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  @nickayivor84323 ай бұрын

  👍

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  @nickayivor84323 ай бұрын

  👍

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  @nickayivor84323 ай бұрын

  👍

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  @nickayivor84323 ай бұрын

  Outstanding tutorial 👌 👏 👍

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  @lindazwane27313 ай бұрын

  Thank you its brilliant

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  @ferdatanyeri13783 ай бұрын

  Beautiful explanation. Thanks a lot.

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  @Mentalista37D3 ай бұрын

  Jupiter’s Great Red Spot, www.nasa.gov/image-detail/47462090512-65ac1cde76-o/ via the #NASA_App

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  @rauanakylzhanov27783 ай бұрын

  Thank you so much now I understand and will ace my test tomorrow 🔥

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  @nm30563 ай бұрын

  So i answered by 1 in an exam yesterday.. Cuz the first form it's looked definite to me .?😢

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  @firstofallbasics18353 ай бұрын

  Well explained

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  @brycevasquez19394 ай бұрын

  Ur the best

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  @user-pp1fp8cx2s4 ай бұрын

  Watching in 2024❤

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  @AshleyTaruc4 ай бұрын

  What app did you use as your calculator sir?

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  @derekowens4 ай бұрын

  I usually use an emulator program called VTI. I would love to find a similar app for the TI-84 Plus CE.

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  @TheAscendedMaster4 ай бұрын

  What you call "visible" light is only based upon your inability to receive the full spectrum and is by no means the standard for all other Energies.