Khan Academy
Khan Academy
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Valence electrons
Views 749Month ago
Mixed number subtraction
Views 1.2KMonth ago
Fractions in context
Views 2.6K2 months ago
Relating fractions to 1
Views 1.2K2 months ago
Comparing unit fractions
Views 6512 months ago


  • david pierce
    david pierce 2 hours ago

    The current educational model is at least two centuries behind the times. The size of a room that holds thirty students allows an instructor to be heard without having to shout. Other than that there is no particular advantage to restricting a group to thirty students. Although technology has changed, the current educational model has not. The internet (RU-clip in particular) allows an instructor to reach millions of students at a time and do a much better job transferring knowledge. If a concept is not clear the lecture can be viewed over and over until it is completely understood. This is not possible with the traditional outdated educational system. A more complete understanding of the subject matter takes time, study and practice, yet all too often course material is just memorized, tested and then forgotten due to time constraints that cannot be avoided in a traditional classroom setting. david

  • 90's Kid
    90's Kid 2 hours ago

    "Tower of Babel". Learn this story from the Bible. You'll get your answer.

  • Sofie Won
    Sofie Won 2 hours ago

    ok watching this in 2019 and I have a question-- so how is the protein processed and "matured" when mRNA attaches itself to a free-floating ribosome instead of one that's attached to an E.R.?

  • Vikashrohit Sharma
    Vikashrohit Sharma 2 hours ago

    This is wrong channel for learn english. Don't teach us error education. Box>boxes not boxen. I am not lol.🤣🤣🤣🤣🤣

  • Ravenstrike721
    Ravenstrike721 2 hours ago

    I thought I was confused before this video. I now know I had no idea what confused really was, until now.

  • KingLegend76
    KingLegend76 3 hours ago

    Argued this with my friend today and he kept saying I was wrong when I was saying continuous is where it is like an irrational number, they can have no ending, no precise number, or infinite values within two numbers, I knew I was right

  • Jonathon Tordilla
    Jonathon Tordilla 3 hours ago

    Thank you Mr. Khan! I've learned so much from Khan Academy, and your lessons allowed me to accelerate my learning by two years! I placed out of Precalculus, Calculus 1, Calculus 2, Chemistry, and Physics, and most of my success is because of your educational videos. I now truly believe that I can learn anything, and I'm determined to make a difference in the world. I hope that some day I can adequately repay you.

  • brooke
    brooke 3 hours ago

    eric out here saving my sat score

  • Evil Devil
    Evil Devil 3 hours ago

    It's very easy to understand, very nice!

  • Winnie Chan
    Winnie Chan 4 hours ago

    the question is in grams or kilograms?

  • Teresa Flores
    Teresa Flores 4 hours ago

    Thank you so much..... Very well explained!!!!!!! Thank you again

  • Obligatory Fail
    Obligatory Fail 4 hours ago

    Watching a 240p video on a 1440@144 monitor, it's crazy how fast the technology has improved over the last ten years.

  • Samuel Amidu Kamara
    Samuel Amidu Kamara 5 hours ago

    Well understood

  • Nikki Aho
    Nikki Aho 5 hours ago

    OMG I LOVE KHAN ACADEMY THERE ONLINE SCHOOLS AMAZING. They are so good at explaining and helping.

  • Sonagi
    Sonagi 5 hours ago

    this has to be the worst explanation yet.

  • Jack Mead
    Jack Mead 6 hours ago

    I like to think of it as "The combined effort of both vectors". Khan Academy is a blessing!

  • Yesha Dalope
    Yesha Dalope 6 hours ago

    I’m gonna fail my midterm exam! I still can’t get it! Am I too slow to not understand how to solve it?

  • Elizabeth Glasby
    Elizabeth Glasby 6 hours ago

    im bored

  • Jam Ace
    Jam Ace 6 hours ago

    Trying to learn hours worth of lessons here right before the exams

  • Valerie Crespo
    Valerie Crespo 6 hours ago

    What if you have to solve for no real solutions with [i]

  • Jazmin M
    Jazmin M 6 hours ago

    you didn't finish teaching the first way before you got carried away into another way.. way too confusing

  • AJ Morrison
    AJ Morrison 6 hours ago

    How does this guy write so neat with his mouse lol

  • prathamesh datar
    prathamesh datar 7 hours ago

    Completed the entire series. Loved it!

  • Moaz El-sawaf
    Moaz El-sawaf 7 hours ago

    Thanks a lot sir <3

  • Grey Ham
    Grey Ham 8 hours ago

    im so confused ap world is taking a toll

  • sanjeev yadav
    sanjeev yadav 8 hours ago

    tax from $10 to $1 KHAN FOR PRESIDENT

  • applebug
    applebug 8 hours ago

    The dreaded stats course :/ WHYYY :/ So difficult for me to retain.

    PHOTON 8 hours ago

    i can never understand the whole projection stuff...Like how does that help me? I see the projection, but how does this relate to the topic?

  • MiddleEastMixTapes
    MiddleEastMixTapes 9 hours ago

    This has to be the most useless thing to learn

  • Sarah Griffin
    Sarah Griffin 9 hours ago

    Thank you so much. This helped me with my homework that I was stressing out about because I didn’t understand. But now I do

  • Ian Petrus Tan
    Ian Petrus Tan 9 hours ago

    at 3:06, khan only took the positive square root of cos y, implicitly rejecting the negative root of cos y. why did he do that?

  • Jayla Cowan
    Jayla Cowan 9 hours ago

    you have to do b'h divided by two and b'h so he is wrong

  • David Brown
    David Brown 9 hours ago

    Holly cow! I didn't know this!

  • Just Because
    Just Because 9 hours ago

    Can you raise your voice just a little bit please

  • إبتسام احمد

    Islam means peace not surrender Muslim means one who submits to god

  • elmotasembella shwekat

    your boring.

  • Angelicom
    Angelicom 10 hours ago

    *please be my math teacher*

  • Courtney McLean
    Courtney McLean 10 hours ago

    the mouse eats the coyote

  • Thuli Ncube
    Thuli Ncube 10 hours ago

    Thank you so much for this simple and understandable tutorial.

  • jmasik100
    jmasik100 11 hours ago

    Typical mechanical explanation. But there is no application as to why. I just need to know the significance of the Standard Error of the sample mean. It's easy to get the figures...but why is the Standard Error necessary?

  • Esha Moha
    Esha Moha 11 hours ago

    i feel that i forget everything since i had 1 year break so i gotta start from the beginning i hope it works out for me

  • Jerry Xue
    Jerry Xue 11 hours ago

    i don get this

  • Md Shajid
    Md Shajid 11 hours ago

    anyone from bangladesh?

  • Saurabh Pimpalkar
    Saurabh Pimpalkar 11 hours ago

    So u mean to say there were no hindu kings ruling in india hmmmm.... See people how they are disorting our history. No Rajput, No maratha, No peshwa.. no cherro, No Sikhs, just only muslims... Waah

  • Fuseteam
    Fuseteam 11 hours ago

    welp now i feel old

  • György Márk
    György Márk 11 hours ago

    this kinda explanations really makes me excited about math :)

  • erolxtreme
    erolxtreme 11 hours ago

    51% of Hugo to stop there, EVEN IF he will not find the card he was searching for.

  • AJ Paulson
    AJ Paulson 11 hours ago

    I’m a sixth grader

  • Gurnoor Aulakh
    Gurnoor Aulakh 11 hours ago

    E N D O P L A S M I C R E T I CU L U M

  • Christina Cao
    Christina Cao 12 hours ago

    8:20 for polyploidy

  • Audio Stories
    Audio Stories 12 hours ago

    I still don't understand🤦🏽‍♀️

  • Behrouz Javid
    Behrouz Javid 12 hours ago

    You had a mistake in the minute 4:30. g(6)=23.2 not 20.

  • Kairy Barazi, M.D.
    Kairy Barazi, M.D. 12 hours ago

    Hi a don’t like math my dad made me watch this

  • Kairy Barazi, M.D.
    Kairy Barazi, M.D. 12 hours ago

    I don’t really like math but I like this ✅ thank you

  • maggie La
    maggie La 12 hours ago

    You are GOD

  • Veronica Leigh Johnson

    My question is do the use of male pronouns prohibit women from becoming President? Can the wording be used by Republicans to challenge the first woman president we get?

  • wethepeople1970
    wethepeople1970 13 hours ago


  • kainat khan
    kainat khan 13 hours ago

    I didn't get the hydrogen bonding part.. if some one can explain please do it

  • Euston Chinhara
    Euston Chinhara 13 hours ago

    how did you draw the graph you lied there

  • Diana Rogava
    Diana Rogava 13 hours ago

    I never understood why water was split into oxygen and hydrogen! Now I do! thank you very much

  • Kevin Ingraham
    Kevin Ingraham 13 hours ago

    this was white people just trying to keep blacks enslaved it's such a pity to think some still are

  • moment ous
    moment ous 13 hours ago

    Most absurd thing ever. Self interest does not lead to good for all atleast in respect to most businesses and corporations these days

  • Maria Khan
    Maria Khan 13 hours ago

    That wasn't complex :( I was searching for more complex ones they give in high school exams here in India

  • Forklift17
    Forklift17 13 hours ago

    8:56 should be "and", not "or"

  • Coco_gacha
    Coco_gacha 14 hours ago

    Thank you You help meh with a quize I have trmorrow 🙂

  • Lamborghini Aventador
    Lamborghini Aventador 14 hours ago

    I meant to type the game sentence

  • GioIn144p
    GioIn144p 14 hours ago

    geez this video helped so much thanks!!

  • I am Beautiful Nora
    I am Beautiful Nora 14 hours ago

    Why did u put minus before a second matrix???

  • mujeebzahir
    mujeebzahir 15 hours ago

  • speed master
    speed master 15 hours ago

    My teacher said watch khan academy s videos he is an amazing person

  • Capitalist Gentleman
    Capitalist Gentleman 15 hours ago

    Thank you for being correct. Anarcho-capitalism is the true right.

  • Sem S
    Sem S 15 hours ago

    my guy took 6 minutes to say 's/n'

  • Dương Dương
    Dương Dương 16 hours ago

    This is a way to be a good math teacher:

  • l h
    l h 17 hours ago

    To learn some things you need a certain level of I.Q and if you don't have that level then you can't learn your way there.

  • Al7ammadi
    Al7ammadi 17 hours ago

    Thank you now I can stude for my SWQ for 9th Grade

  • Andrea Duran
    Andrea Duran 17 hours ago

    I get this and wrote notes and everything but my equation is 5x^2+10x+6 and I got stuck. Can someone explain to me please

  • A Montenegro
    A Montenegro 17 hours ago

    I love khan academy! 😍

  • Jimmy Arce
    Jimmy Arce 18 hours ago

    Thank you Sal for doing your best at giving access to education to everyone at every place and time as it should be!!! Much respect!! (:

  • upendra kumar
    upendra kumar 18 hours ago

    This is worst video

  • Adam H7
    Adam H7 18 hours ago

    Computational Mathematics has me permanently glued to this channel

  • America Lost
    America Lost 18 hours ago

    The Republican Party is the party of cowards and hypocrites who couldn't care less about the country and its Constitution as long as they get reelected. SHAME!

  • J K Lee
    J K Lee 19 hours ago

    Why couldn't he just pick squirrels instead of rabbits if his Freudian slip keeps calling out squirrels?

  • Rodrigo Marinho
    Rodrigo Marinho 19 hours ago

    I took a different approach. Since sqrt(c) is not an integer, and is the sum of two other Square roots, then sqrt (c) = z.sqrt(k), sqrt (b) = y.sqrt(k) and sqrt (a) = x.sqrt(k), thus z = x + y. Let's say b is the smaller, so a = 60 + b. But b = y².k, so a = 60 + y²k = x²k. x²k - y²k = 60 k(x+y)(x-y) = 60 Sum and difference must be both odd or even. For the 1st case, k = 4, which is a perfect square and goes against the fact that it can't. So k = 3, 5 or 15. k = 3 has x = 6 and y = 4 k = 5 has x = 4 and y = 2 k = 15 has x = 2 and y = 0 So a is Max when x = 6, and k = 3, which gives us 108. Therefore b = 48. 108+48=156

  • Arsema H
    Arsema H 19 hours ago

    This is the best .It really helps to understand its concept and is easy to understand. for those of you who haven't seen it yet check it out.

  • tony duvall
    tony duvall 19 hours ago

    You sir are best teacher I've ever hard. Thank you.

  • nirmal saha
    nirmal saha 19 hours ago

    But , where is PIE language?

  • ItsUr Mom
    ItsUr Mom 19 hours ago

    Pleass donate for khanacademy

  • danish Ali
    danish Ali 19 hours ago

    Hindi me samjaeo

  • Wade Brink
    Wade Brink 19 hours ago

    thanks for helping me i was scared to ask much teacher you a life saver Khans academy :)

  • Ayan Dalal
    Ayan Dalal 20 hours ago

    What the heck is the lady doing on the side of the screen.

  • It'sCurryAndRice PlusWater

    I'm watching this and my midterm exam is tomorrow

  • Elena Olivare
    Elena Olivare 21 hour ago

    I think i can understand you more than my teacher in math

  • Sniber shot
    Sniber shot 21 hour ago

    anyone from 2019

  • Henry Collins
    Henry Collins 21 hour ago

    What about inflation, bank charges, tax?

  • Tatyanns
    Tatyanns 21 hour ago

    Fructose carbonyl is in the middle vs Glucose is on the end

  • Stella Galenzoga
    Stella Galenzoga 21 hour ago


  • Izaan Shaikh
    Izaan Shaikh 21 hour ago

    I wish you replace my school teacher

  • Colin Latham
    Colin Latham 21 hour ago

    EBITDA can sometimes be used to distract investors from the lack of real profitability. EBITDA in the 1980s was used as a tool to assist with leveraged buyout investors examined distressed companies that needed financial restructuring. They used EBITDA to calculate quickly whether these companies could pay back the interest on these financed deals. in the 1980s to measure a company's ability to service the debt used in a leveraged buyout (LBO). During the "dot com" bubble when companies had very expensive assets and debt loads that were obscuring what analysts and managers felt were legitimate growth numbers. In conclusion EBITDA does not fall under generally accepted accounting principles (GAAP) as a measure of financial performance. Because EBITDA is a "non-GAAP" measure, its calculation can vary from one company to the next. Note: EBITDA does not fall under GAAP generally accepted accounting principles .

  • Leena Chauhan
    Leena Chauhan 22 hours ago

    This video helped me on my home work

  • Sakeena Zehra Gulzar
    Sakeena Zehra Gulzar 22 hours ago