His passion is contagious. Learn something from everything and learn EVERYTHING from SOMETHING; then tell that something to the world with all the passion you can.
+Sixtall baller There is a logical reason to not teach this in schools, at least until students learn Algebra I as knowing the method without its justification may end up being detrimental in the future as innovation depends on seeing and using the justification, not just the method.
If you want to learn this and use this actively you can either study by yourself or ask your schools math team coach, you should learn a new trick to actively use every week(Depending on the frequency of the meets)
No but seriously as I never say this to someone, this man is not only intelligent but very likeable. I watched many of his videos and he seems like a real nice man.
Math is an art, and I think this guy definitely "Beat the devil" out of Bob.... (Note Bob said in like, every video when cleaning your brush to "beat the devil out of it.)
@@casey-gt8nl It isn't meant to work for most math principles. It's only intended for squaring and what makes it illogical? It is a reliable method for squaring.
@@intergalacticraisins8985 but it is not that logical, it's just mnemotechnics. where's the logic if you can't follow the same procedure for any number?
@@intergalacticraisins8985 also not that really practical at all. have you seen the mess that 98^2 got into? tell me that's easier than multiplying 98*98 or if you want it 100^2 - 98*2
@@eldiegoasecas what numbers doesn't it work for? 98^2 is just 96*100 which is 9600 plus 4 so 9604. You wouldn't need to use this for 100^2 because obviously it's just 10000. Just because there is a faster method in some situations doesn't mean it's illogical.
This really made me happy. I'm tearing up now. I have always been bad at mental math and people would make fun of me. Just his whole energy and making me learn step by step is such a nice feeling.
Thank you Sir. Amazing . Sir, yours videos helping me to teaching in schools. It helping 100s of poor children in learning maths easily.. Yours service is unforgettable... Thank you
I've watched several of Arthur Benjamin's videos on youtube and I find them fascinating. In another one, he says that he starts saying the answer to a problem before he has worked out the whole answer (an advantage of working left to right). At 9:20, when he says "19 Million", he doesn't know what the rest of the answer is, but he knows it's 19 Million and something, so just says "19 Million" so that he can get it out of his head while he works on the rest of the answer. I find it even more fascinating that he says that by the time he gets to the end of his answer, he sometimes can't remember what the beginning of it was. I can really see that in his answer to the last problem. I wouldn't be surprised if he forgot the answer started with 19 million by the time he had verbalised the whole answer. He is an amazing entertainer and teacher!
This is wonderful. I have the audio versions of "The Joy of Numbers" and "The Joy of Math," as well as "Mathemagics," but having this audio-visual format is a great advantage.
to find the year code start by dividing the year by 4 to the nearest whole number. For example if the year is 43 dividing by 4 we get 10. Now 10+43 = 53 and 49 is a multiple of 7 so we are left with 4. If it's 2043 then we are done and the year code is 4. If it is 1943 we need to add 1, so the code is 5. This gives the year codes 1900-2099
Every time he drew a smiley face in the 0s I had to pause the video because I was laughing. It was just so unexpected at first. But thinking about it, it's actually a pretty good way to teach someone to multiply numbers with a bunch of zeros on the end because then you don't forget them even if you aren't using them in the initial calculation. And it's awesome.
His enthusiasm is infectious. I had a math teacher similar to him. She was big on hard work though. A lot of students didn't like her. Somethings are no pain no gain. Maybe he could have made it easier.
Arthur Benjamin, Professor of Mathematics at Harvey Mudd College, explains the fundamentals of performing mental mathematics. This video was produced for Mathematics Awareness Month, 2014. Visit www.mathaware.org for more.
I have a similar trick for 2 digit numbers: lets say 41 where 4=a and 1=b ==> your first digit is a^2 = 16 you next digit is 2ab = 8 and your last digit is b^2 = 1 :: which gives you 1681 (if 2ab>10 then carry the tens or hundreds to the answer of a^2; same rule if b^2>10)
Actually, if you think of the "first" (i.e. the tens) digit "a" as 10a, then the binomial expansion of a two digit number is (10a + b)^2 = (10a)^2 + b^2 + 2(10a)b =100a^2 + b^2 + 20ab. To square let's say 57, 57^2 = (50 + 7)^2 = 50^2 + 7^2 20(50)(7) = 2500 + 49 + 700 + 3249.
the square thing is really useful, an explanation of how it works is if you have x and want to find x^2. Do: (x-a)*(x+a) = x^2-a^2. But we want just x^2, so we add the a^2.
The intro xDD "What should we do guys?" "Just stare into the camera smiling.. don't stop smiling!" "You made a photo already?" "It's a video dude" I wonder why he is not advertising his book "Secrets of mental math".. he is explaining stuff like this there and a lot more. He also shows you how mentally calculate the day of the week for any given date. I made a youtube video about his method, in case anyone is interested. But seriously, if you like stuff like this, you gotta get his book.. it's awesome!
Entire thing is based on a book "VEDIC MATHEMATICS" by Sri Bharati Krsna Tirthaji. He decoded these principles / sutras from Vedas, which is a Hindu's text originally written in Sanskrit around 5000 years ago, and before that this knowledge was passed orally from . You could buy this book from Amazon.
"Vedic Mathematics is a book written by the Indian monk Bharati Krishna Tirtha, and first published in 1965. It contains a list of mathematical techniques, which were falsely claimed to have been retrieved from the Vedas and to contain advanced mathematical knowledge. "Krishna Tirtha failed to produce the sources, and scholars unanimously note it to be a mere compendium of tricks for increasing the speed of elementary mathematical calculations sharing no overlap with historical mathematical developments during the Vedic period. However, there has been a proliferation of publications in this area and multiple attempts to integrate the subject into mainstream education by right-wing Hindu nationalist governments." From en.wikipedia.org/wiki/Vedic_Mathematics Note: Many of the scholars who debunk his claims are themselves from India. They don't dismiss the techniques, acknowledging them as valid techniques. They simply debunk his claims of them being the result of ancient knowledge, unknown to modern man.
Awesome stuff! The hardest part of understanding this video was trying to figure out what was "off". Something was getting to me. Then I noticed he missed a belt loop on the back of his pants. I hate those pants with two loops in the middle of the back.
This guy reminds me of the young lad from That's My Boy. I can hear him answering the arithmetical questions from his admiring fans and saying "bih-boo-bih" **in a robot's voice** "the answer is [answer]"
It is quite possible that he was the first to use the squaring trick after all, once the idea is out it will spread, and there's nothing very difficult about the algebra (the real insight is seeing that it can be used for mental calculation).
You’re such a great teacher! I wish you were MINE though... You teach so clearly, but I really want to be able to square any 2 digit number in my HEAD?
LOL I'm old now, but I used to be a super genius; did math in my head routinely (still do, but have no need for more than basics nowadays), but I never heard of any of this.
He's impressive with the mental arithmetic calculation of large numbers.. He did- however, two tricks that I frequently use with my friends: (1) Giving the missing digit of a product. (This is based on the divisibility by nine), (2) Day-of-week calculation (With practice, I am quite adept and fast using the Doomsday Algorithm devised by mathematician John Conway),
For me, when I was a kid, my favorite number was 10. Why? Because whenever you multiply any number but zero the thing you only have to do is to add 0 at the very end of the number.
