❖ LaGrange Multipliers - Finding Maximum or Minimum Values ❖

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  • Опубликовано: 22 янв 2025

Комментарии • 914

  • @patrickjmt
    @patrickjmt  5 лет назад +171

    Hi all! Please post comments, questions and anything else on your mind in the comment section! While I try to answer as many questions as I can, there are more questions than I can answer by myself so if you are someone who might be able to help, please do so! The community is so much better when everyone is involved and helping each other out. Our strength is our willingness to help each other!
    Also please feel free to like or dislike the video. Your feedback is always appreciated so that hopefully I can make my future videos the best possible! Thanks and happy studies!

    • @dchill4086
      @dchill4086 3 года назад +1

      One thing you forgot to mention is how much harder math is when you can't hear the sharpie noises. Seriously though your videos are awesome and the sharpie ASMR is legendary. Thanks!

    • @youtune8453
      @youtune8453 3 года назад +1

      Omg i cant believe im trying to study something who explained 13 years ago, almost when i was 5 yrs old
      Ok before watching the video i read your comment you are so sweet sir...
      I have a question my lecture explained somewhat in different manner she said F=f+ lambda pie
      Where F is what we have to find
      f is constrained eqn
      Pie is function
      My question is how to say which is constrained eqn and which is normal eqn,In question i can see two functions
      I hope you will reply its been sooo long this video got uploaded
      And i think this msg will notify your previous videos
      Waiting for your reply sir!!!!

    • @tinyasira6132
      @tinyasira6132 3 года назад

      that's so kind 😊 we should all help each other ❤

    • @AzikIlhom
      @AzikIlhom Год назад

      Thanks

  • @patrickjmt
    @patrickjmt  16 лет назад +462

    sometimes i watch my own videos when i forget how to do stuff! i can summon my old powers!

    • @Hi_Brien
      @Hi_Brien 3 года назад +5

      I also tend to go back to old videos when I need a refresher! I randomly was asked to tutor since I'm a math major at the library, and they were like "working on Lagrange multipliers" I was like "Minimum? Maximums? How'd that work again?"

    • @Hi_Brien
      @Hi_Brien 3 года назад +3

      @@prince29999 there are two ts there, I'm a lover of math who wears a hat.

    • @Hi_Brien
      @Hi_Brien 3 года назад +2

      @@prince29999 but it is getting better :)

    • @4b1saisrinivas2
      @4b1saisrinivas2 3 года назад +1

      13 years

    • @Goku17yen
      @Goku17yen 3 года назад +1

      @@4b1saisrinivas2 😂

  • @patrickjmt
    @patrickjmt  16 лет назад +161

    u did a good job old me! i remember now! thanks!

    • @AtikaTahsinSaba
      @AtikaTahsinSaba 3 года назад +1

      Wow XD

    • @mocha6315
      @mocha6315 3 года назад +3

      @@AtikaTahsinSaba you know this video is very old when the comment itself is 12 years ago lmao

  • @SquidwardsMoney
    @SquidwardsMoney 10 лет назад +84

    Patrick,
    I'm sure you've heard this thousands of times already, but your videos are nothing short of amazing for saving peoples' grades and explaining concepts. Thanks so much!

  • @geenstagni1060
    @geenstagni1060 4 года назад +38

    Gosh I absolutely owe my life to you! I simply cannot believe that I was able to learn something that was 77 slideshow slides and way over my head through a single example in less than 10 minutes!! Sincerely, thank you SO MUCH for what you do for students!

    • @patrickjmt
      @patrickjmt  4 года назад +3

      Glad I could help! come back any time :)

  • @wk961
    @wk961 6 лет назад +39

    dude, i've been watching your videos since my first college algebra class ten years ago in community college. Now, I'm getting my engineering master's and I'm taking a class in numerical optimization. I literally couldn't believe you have a video on this obscure topic! Thank you.

  • @anthonyaddo
    @anthonyaddo 8 лет назад +314

    Incredible I learn in ten minutes what a professor bumbles along about for two hours.

    • @roslin8060
      @roslin8060 8 лет назад +33

      Well, that's probably because it's accompained by a whole bunch of formal math theory, not just a recipe on how to calculate exercises. :P

    • @stephaniecurry45
      @stephaniecurry45 5 лет назад +9

      Ros Lin I mean this is more useful honestly

  • @Foxoq
    @Foxoq 9 лет назад +776

    One day I'm gonna graduate and send you a cheque. Thanks Patrick.
    Edit: Yes I graduated. 😂

    • @patrickjmt
      @patrickjmt  9 лет назад +173

      +Jordan S you can donate a dollar a month and patreon and i would be happy :)

    • @sanjaykrish8719
      @sanjaykrish8719 8 лет назад +19

      Patrick I am in India. Is there a way to donate to you in rupees

    • @m13m
      @m13m 8 лет назад +4

      Sanjay Krish yeah debit card

    • @xmj1279
      @xmj1279 7 лет назад

      Jordan S feels👍👌👌✋✋✋✋

    • @DioGaming1611
      @DioGaming1611 6 лет назад +13

      Jordan S did you graduate?

  • @tripleS9000
    @tripleS9000 6 лет назад +3

    Thank you. I never comment on videos but you literally cleared up an entire semester's worth of confusion from my econ class. Prof introduced this but never went in anywhere near as much detail in solving this as you have.

  • @tiffanysteytler627
    @tiffanysteytler627 2 года назад +6

    Patrick, i passed my calculus exams because of your videos. I went from literally 3% to 52%. I am enjoying maths and it's all because of you. you not only make maths fun, but it's easy to comprehend and remeber. thank you:)

  • @Frixos000
    @Frixos000 11 лет назад +45

    I love you dude.... you have saved my ass in so many exams

  • @amymantilla9685
    @amymantilla9685 3 года назад +2

    wow you're still helping people even in 2021! I've been struggling with this concept for weeks now and after this video i finally understand wtf im supposed to do LMAO
    king.

  • @WilliamSprecher
    @WilliamSprecher 9 лет назад +121

    Dont be afraid to plug the site! Keep plugging! Keep the paper there longer!

    • @patrickjmt
      @patrickjmt  9 лет назад +41

      +Willballhead ok, good idea, i will

  • @sydneystraver
    @sydneystraver 8 лет назад +6

    Honestly wouldn't get my business maths without all these videos! Thanks for everything!

  • @kwanele1253
    @kwanele1253 9 лет назад +6

    WOW, its started like boring, but i told my self i have got to pay attention. WOW, very nice explanations, clear in my mind. indeed so confident at the moment. THANKS A LOT

  • @freeway7979
    @freeway7979 5 лет назад

    I have had many math professors taught me but Patrick is the far better teacher than any professor I have ever had. Thanks a million!

  • @patrickjmt
    @patrickjmt  13 лет назад +3

    @gumlese oh yes, i did used to teach at those places. i never used slides or a projector; i always hated that method as a student. but it was the traditional ' writing on the board and talking ' method. not the most effective i think honestly, but that is how they wanted it done.

  • @PaperAdept
    @PaperAdept 13 лет назад

    I think I love you. 10 minutes and you made all of that make sense, a feat neither my professor nor my book could do.

  • @lifewithdylan
    @lifewithdylan 7 лет назад +58

    I will pass the maths side of my degree thanks to you! if your ever in London ill buy you a pint or 10

    • @patrickjmt
      @patrickjmt  7 лет назад +5

      hoping to be back there one day :) congrats!

    • @t0lg4drc15
      @t0lg4drc15 6 лет назад +1

      Did you pass your exam? :D

    • @leskipbayless3280
      @leskipbayless3280 4 года назад

      @@t0lg4drc15Check his videos he got one of the best grades in his year group at University

  • @autogordel
    @autogordel 12 лет назад

    patrickJMT making this world a better place with his free knowledge. And making my gradelist better. Thanks so much man.

  • @GajuGatera
    @GajuGatera 8 лет назад +7

    You might have just helped pass my exam tomorrow! Thank you so much!!!

  • @bryanaustin22
    @bryanaustin22 6 лет назад

    ive been watching all of your videos throughout my college career. you are the best math teacher i have ever seen. thank you so much

    • @patrickjmt
      @patrickjmt  6 лет назад

      thanks so much, i appreciate your kind words :)

  • @patrickjmt
    @patrickjmt  16 лет назад +4

    thanks for helping! i get sooo many questions a day, i just can not answer them all! : )

  • @dtranscend
    @dtranscend 12 лет назад +1

    Dude I know that you've heard this a million times, but thank you so much. I've had pneumonia this semester and missed over 3 weeks of class. I would be retaking calc III next fall if it were not for you and your amazingly concise videos. Actually I've found that I seem to get a more intuitive grasp on these concepts learning from your videos compared to classroom time, and the combination of both is absolutely outstanding. You've saved my bacon and I will recommend you to everyone. THNX!:)

  • @philipwest2551
    @philipwest2551 5 лет назад +5

    Thanks for the video: I think that when you obtain 12x - Lamda = 0 and 24y - Lamda = 0 you should simply note that 12x=24y or x = 2y and substitute THAT into the third equation. It's a lot easier in this case!

  • @naras987
    @naras987 14 лет назад

    PatrickJMT, you are the savior of many a calculus student. You are a superior teacher to tons of professors including top tier schools. Please take these comments as motivation to keep providing quality instruction to the masses.
    seriously, these are great.

  • @LaverneADavid
    @LaverneADavid 7 лет назад +4

    How did you get -3 lambda over 24?

  • @georgeanons301
    @georgeanons301 11 лет назад +1

    Patrick ---> Fast, to the point, learning with full information (great for cramming) Relevant practice problems that help you understand the material.
    Khan ---> Conceptual intuitive explanations. Good for in depth understanding. Also good to prime you for Patrick's videos.
    Textbook ---> Reading math is impossible.

  • @JorSex
    @JorSex 15 лет назад +6

    Awesome video.
    I have one question, sometimes i've seen:
    f(x) + λ(constraint) instead of
    f(x) - λ(constraint)
    Is there a difference?

  • @aeaeae13
    @aeaeae13 3 года назад +1

    Like alot of other people, I got my exam tommorow morning and it's currently 2 am.
    Gosh, you've helped alot of people over the decade what a nice feeling that must be!

  • @Shafique96
    @Shafique96 9 лет назад +10

    On similar videos and other examples I see a positive sign when setting up the lagrange? ( f(x,y,z) + L(g(x,y,z)-k). And other times I see it set up like how you showed in this example. Are both ways acceptable?

  • @jamesblu1146
    @jamesblu1146 6 лет назад

    I'm looking at all these comments from 2 years ago, and I just wanted to say that your videos are helping me pass calculus3 in 2018. Cheers Patrick

  • @NitishDobhal
    @NitishDobhal 9 лет назад +9

    nice one that explains HOW (not why) it works! :)

  • @Maximo10101
    @Maximo10101 12 лет назад

    You make it so easy. I was reading my lecture notes, my tutorial notes, the Calculus book, scratching my head for an hour. Watch your video for a couple of min and it makes sense! Keep up the great work!

  • @olyadmulisa6825
    @olyadmulisa6825 10 лет назад +11

    so you dont know if you are minimizing or maximizing ?
    you have to do a trial and error?

  • @messididit
    @messididit 4 года назад

    you are actually helping people you probably have never expected of. thank you so much!

  • @Norbizzle2012
    @Norbizzle2012 10 лет назад +3

    My professor never liked LaGrange Multipliers because of the nasty system of equations that could arise. Instead, he taught us to turn the function f(x,y) into a function G(x,y(x)), G(x(y),y), or G(t) by using the constraints or through parametrization and ending up with a function G of only one variable. In this problem for example, using the constraint, you could say that y=90-x and that G(x,y(x))= 18(x^2)-2160x+97200. Using the first derivative test, you come to the same conclusion that 32400 is a min of that function. There are obviously times when you can only use LaGrange Multipliers, but if it is possible to use this method, it is much easier.

    • @lebeobachter
      @lebeobachter 9 лет назад

      Norberto Torres while this is really a more effective way in this case, it is not always possible to express one variable as a function of the other

    • @danielgates7559
      @danielgates7559 6 лет назад

      Actually for this example you can just use Cauchy-Schwarz Inequality and destroy this problem instantly...

  • @vasundharasontakke6503
    @vasundharasontakke6503 2 года назад

    the explaination is so crisp and clear and you handwriting is so clean, all of this makes it look so simplem thanks

  • @kushagragupta97
    @kushagragupta97 9 лет назад +11

    If we have exactly the same way of finding maximum or minimum , and if lagrange's multiplier gives the minimum of a function but we have to find its maximum how do we do that?
    Like if in your example we have to find maximum cost
    How do we do that?

  • @sruthikagrandhi2740
    @sruthikagrandhi2740 10 месяцев назад +1

    Hi i just saw ur video it helped me a lot i got all my questions clarified thank you 😊. I just saw that it was uploaded 15 years ago i was in shock

  • @DANGJOS
    @DANGJOS 10 лет назад +41

    how do you keep that sharpie perfect in every video?

  • @Jurkblot
    @Jurkblot 9 месяцев назад +2

    Insane that 16 years ago I could have been watching this but instead I was 5 watching Fred 😔✊🏼

  • @Mu5hu501
    @Mu5hu501 11 лет назад +8

    lol way to help me figure out in 10 min what me and my teacher couldn't do in a couple days

    • @and1fer
      @and1fer 10 лет назад +4

      If you hadn't done those couple days of trying to figure out, you must probably wouldn't understand it. Everything counts. That's reason why we go to lessons although our teachers might not be that good.

  • @madameneruda
    @madameneruda 15 лет назад

    you're the freaking of tutoring Patrick. Thanks a million for what you're doing

  • @modibacm2783
    @modibacm2783 6 лет назад +11

    How do we know if it's maxima or minima?

  • @hejhowareyou
    @hejhowareyou 12 лет назад +1

    I play you videos while listening to slowcore because you voice is so soothing.

  • @HT-rq5pi
    @HT-rq5pi 10 лет назад +3

    Is there a video explaining the concept/proof behind this method? I can apply the brute force method behind solving this, but I want to actually understand this - i've tried looking up various websites but they are too complicated as they prove general results for n dimensions.

    • @samajapstaceht
      @samajapstaceht 10 лет назад

      Look up a course on the calculus of variations. You'll probably need some analysis training, but that will tell you all that you need to know.

    • @brenxbux
      @brenxbux 10 лет назад

      go to class

    • @HT-rq5pi
      @HT-rq5pi 10 лет назад +2

      i'm not a college student, I am learning from home.

    • @brenxbux
      @brenxbux 10 лет назад +2

      i skip so much class i thought you did too xD

    • @awitzk
      @awitzk 10 лет назад

      Hey man. A very basic explanation is that this method finds the points at which the gradient of the constraint equation (direction of maximum increase) matches the gradient of your objective equation. Imagine level curves of the constraint equation and the level curves of the objective equation on the same graph. This method scales the constraint equation to where the directions of maximum increase are equal. Its easier to see if you re-write the method as (Gradient)F= lamba*(Gradient)g. F being the objective function and g the constraint.

  • @Moonwalkerdrey
    @Moonwalkerdrey 6 лет назад

    this video was uploaded 10 years ago and here i am learning from you. thank you so much!

  • @poetryaddict1
    @poetryaddict1 7 лет назад +25

    The way he says "Lagrange" sounds like the way that one Vine says "Lebron James" lol

  • @GooseyFruit
    @GooseyFruit 14 лет назад

    your a very good teacher man, straight to the point and with no accent, gotta love it! keep up the good work, highly appreciated(y)

  • @patrickjmt
    @patrickjmt  16 лет назад +3

    haha! good luck with everything!! : )

  • @kendylharvey660
    @kendylharvey660 4 года назад

    Thank you so much for actually explaining step by step what you are doing to solve the equation. I have watched so many videos that don't explain key parts in solving it and it's been very frustrating. You're awesome!

  • @izzyxyoung
    @izzyxyoung 8 лет назад +7

    Wow, I just realized I could use this to diversify my stock portfolio better. Thanks so much!!

    • @EagleLogic
      @EagleLogic 7 лет назад +1

      TheDarkKnight2124 Well you could create a function with let's say two variables. z = ax + by where a and b are constants. a represents the price of stock a and b represents the price of stock b. x and y is the stock quantity. Say you desire 90 stocks. You then have x + y - 90 = 0 for lambda. z = ax+by for your main function. Then you can proceed with the methods from this video.

  • @treylitefm
    @treylitefm 13 лет назад

    You've taught me more in this 10 minute video than I've learned in the last two weeks of calc. Thank you, bro. You're a lifesaver.

  • @pd7009
    @pd7009 8 лет назад +7

    what if we wanted to maximise this equation?

    • @TheBossStuart
      @TheBossStuart 8 лет назад +2

      Petr D look at the function. Making more TV A's (x) is more expensive than making TV B's (y). So just make 90 tv A ;-)

    • @jankaas9256
      @jankaas9256 8 лет назад +2

      Maximising applies to other equations. For example an equation for Profit. Maximising this function is no different from minimising a function. Its always the same: (the function you want to min- or maximise) - λ x (constraint).

  • @AncientWord1
    @AncientWord1 4 года назад

    Can't stop feeling grateful to you. U made me understand this thing so easily. In Kenya,, am thankful

  • @mortalas100
    @mortalas100 10 лет назад +3

    You do not subtract the constrant , you add it to the original function.

    • @YoungColCol
      @YoungColCol 10 лет назад +2

      You can do either since G(x,y)=0 (x+y-90=0)

  • @arber622
    @arber622 11 лет назад

    Taught so much better then my uni prof who gets 100k+ a year and my textbook that cost 150$... He might as well just show your videos in lectures, thanks so much @PatrickJMT !!!

  • @Risate
    @Risate Год назад +10

    bros 14 years older now

  • @jaredtkatz
    @jaredtkatz 14 лет назад

    this is awesome. i go to MIT and this video makes more sense than the professor's lecture. Thanks a ton!

  • @francistembo650
    @francistembo650 9 лет назад +4

    you sound like that guy Mr Mackey from south park lol

  • @WalkerDestroyer
    @WalkerDestroyer 14 лет назад

    One of the only tutors on youtube that can give khanacademy a run for it's money.

  • @eff700
    @eff700 10 лет назад +3

    O.O he's left handed!

  • @garytuortojr7338
    @garytuortojr7338 8 лет назад

    You don't even know how helpful this is. I have only taken up to Calc 1 but am currently back in school pursuing a master in economics and in my Micro class we used lagrange for consumer demand theory and I was just completely lost thanks so much for this! The partial derivative stuff threw me off but they're really just the same thing as a "regular" derivative.

  • @donaldwilson3579
    @donaldwilson3579 7 лет назад +6

    God I hate math

  • @prudenciojoaomuchanga7267
    @prudenciojoaomuchanga7267 7 лет назад

    This video was posted in 2008 and it's 2018 now and it is still of great help! Thank you Patrick!! :)

  • @Mathiology
    @Mathiology 13 лет назад

    YOU ARE AMAZING ! I always watch your videos and learn from them , and I always recommend my friends to watch your videos. I don't know what to do without you !! MAY GOD MAKE YOUR LIFE LONGER !

  • @Lamorak117
    @Lamorak117 12 лет назад

    I just wanted to thank you for the help. I'm still working on Lagrange Multipliers but this video helps a lot. We have to use these all the time for my upper division Economics course and my professor did a terrible job at explaining. So thanks again!

  • @bachstrad644
    @bachstrad644 13 лет назад

    Thank you for all your help. Every time I watch one of your videos I click on the google ad. This is my way of donating to you :)

  • @killshot2065
    @killshot2065 4 года назад

    First time in my life watching someone writing with left hand live. I know people also write in left hand but i have never seen that with my own eyes.
    Btw, Thanks for this awesome video.
    :)

  • @scycon21
    @scycon21 16 лет назад

    Simply an amazing teacher. I left lecture thinking "What the hell was that" and I come to RUclips to find Mr. patrickJMT and now I am confident!

  • @dinosoup
    @dinosoup 6 лет назад

    Most straight forward and quality explanation on this website

  • @cegley21
    @cegley21 9 лет назад

    Thank you for your videos. You talk nice and slow, and actually explain things! You are quite literally saving my grade!

  • @redechoes2081
    @redechoes2081 14 лет назад

    Wow. I wish I would have found you earlier! My Calc final is tomorrow and I've literally just been going through all your videos. This seriously is amazing. It makes a huge difference when you can try a problem and then watch someone do it step by step. Thanks so much!

  • @MarksmanBryan
    @MarksmanBryan 12 лет назад

    I got a 5 on my AP Calculus BC exam last year because of your videos! I missed a day of my Calc III class (lol, overslept) when my professor talked about Lagrange multipliers. I wouldn't have been able to finish the last question on my homework without your help! Thank you!

  • @craig5716
    @craig5716 9 лет назад

    My calc class keeps getting smaller and smaller every week, and class averages are hovering around 58%. I'm just smiling there knowing I got Patrick to help me out. Best tutor/TA and it's free.. unreal!

  • @patrickjmt
    @patrickjmt  16 лет назад +2

    no, i have not done that particular example, or any others with lagrange multipliers. perhaps i will make one tomorrow though!

  • @Simmiebird
    @Simmiebird 7 лет назад

    Best Lagrange explanation in RUclips thank you.

  • @21esanch
    @21esanch 13 лет назад

    Ive been watching your videos since i was in calculus 2 no words can express how grateful i am to u111 thnks man!11

  • @pulechishimba9502
    @pulechishimba9502 6 лет назад

    you explained it better and made Lagrange multiplier easy to understand. best Lagrange multiplier tutorial

  • @austinsouza5002
    @austinsouza5002 7 лет назад

    You just made my life so much better, I can't tell you how much i appreciate this video

  • @lokithor83
    @lokithor83 13 лет назад

    i've studied this topic years back but due to negligence, i've lost it.. i found it back today clearer than ever.. thanks..

  • @abhijitnayak5445
    @abhijitnayak5445 6 лет назад

    the best optimisation in engineering teacher I hv ever come across

  • @oguzozturk6402
    @oguzozturk6402 6 лет назад

    I was trying to understand the math behind the Support Vector Machines algorithm, and it was using lagrange multipliers method because of constraints, you helped me a lot to deal with it in 10 minutes, loves and respects from Turkey :)

  • @KingBueno619
    @KingBueno619 11 лет назад

    My professor taught me this today and skips so many steps. This video is very clear and very understandable. Thanks Patrick!

  • @shen1266
    @shen1266 2 года назад

    I want to thank you for how i survive math classes because of your videos, thank you so much 💖

  • @oexnorth
    @oexnorth 15 лет назад

    perfect perfect perfect. My textbook does not explain it at all like this. Now it seems so much easier. Thank you.

  • @hurolinci5986
    @hurolinci5986 6 лет назад +2

    Why do you make me understand it so easy whereas at uni they make it look so hard...
    Cheers mate!

  • @iffatsarfraz5145
    @iffatsarfraz5145 4 года назад +1

    Thank you so much patrickJMT for all of your amazing videos! Years ago, I passed the AP Calculus AB and BC exams because of you!

  • @superman3621
    @superman3621 12 лет назад

    i never thought i would say this but...you make math FUN!. honestly, thank you.

  • @SplatterBacks
    @SplatterBacks 12 лет назад

    Your videos are great refreshers of material we covered a long time ago that has since become a little hazy. This is great stuff, thanks a bunch.

  • @effortless35
    @effortless35 12 лет назад +1

    The maximum cost will be on the boundary (specifically y=90). Technically we should have checked (x=0,y=90) and (x=90,y=0) too, I think.

  • @davidfield5295
    @davidfield5295 8 лет назад

    Excellent explanation, it's very helpful that you walked through an example instead of just presenting a conceptual framework

  • @Zerpyderp
    @Zerpyderp Год назад

    14 years later and i still watch ur vids, thanks amigo

  • @lowekygoodlooking434
    @lowekygoodlooking434 7 лет назад

    Im so happy that theres people like you here that can teach me some real math

  • @seinfan9
    @seinfan9 13 лет назад

    Up all night studying for my vector calculus final in the morning. You rock, dude!

  • @OceanBagel
    @OceanBagel 12 лет назад

    Your videos are awesome! I've been watching them to prepare for a test in multivariable calculus, and although you don't have a video for every topic, you cover almost everything, and in about half the time of other lectures. Even though I haven't had a formal class in multivariable calc, your videos allowed me to learn most of the topics covered in three days. Thanks a lot!

  • @rosuchoach704
    @rosuchoach704 7 лет назад

    you are awesome Patrick. I'm from Bangladesh, and your videos help me understand maths more than my typical class lectures.

  • @93runninggiraffes
    @93runninggiraffes 5 лет назад

    This is awesome. Needed to recall this stuff for application in an upper level graduate course in maths, and this is the first thing to actually bring clarity again. Thanks so much!!

  • @patrickjmt
    @patrickjmt  13 лет назад

    @gumlese what do you mean ' for lectures ' ? i am not employed by a school / college / university