He already got a new pen and everything looks clearer now, I try to avoid his videos with the old pen and try to look for another one about that same topic
This is one of the best things to come from the internet (imho) - an altruistic push towards free, quality education available to anyone. Not only that, but the teaching methodology improves over time, so the learnability and retention of material can improve for students of all backgrounds! Loved Sal's TEDTalk on AI and Education, he's a true pioneer.
This is one of the best channels on TH-cam and I feel so sorry for fellow students who haven't come across it yet. You've made me fall in love with calculus. Thank you
I also want to once again thank Sal, and all the people that make these videos possible. Most of us realize he was the driving force, but other people have contributed aswell. These videos helped me through my precalc course to end with a high B after coming in way behind not knowing alot about algebra. They are now helping me learn physics and the calculus behind the calculations for the equations. Thanks again guys/girls, and special thanks to you sal, for being such a great teacher.
My teacher looks useless next to this, I would like to thank you for saving my university place for September...I was about to fail calculus. I could not understand a thing, until now. Thanks so much!
Sal, you're a genius. Why can't everyone explain as well as you do? Whenever I'm stuck in my mathbook, I look at your vids and it's just crystal clear. Thank you :)
So many comments of thanks, but I feel the need to add mine as well. Many thanks for taking your time to spread free education, especially on such a vast scale. It is truly a marking point in the evolution of man when learning becomes viral. It truly marks a point in the evolution of man, as we approach perfection. What an honor Mr Khan.
Not sure why everyone's guffawing over the "I'm 15 years old" comment. It's not hard to watch a video on TH-cam when you're 15. As long as you're not intimidated by the idea of calculus, learning it from Khanacademy isn't any harder than learning arithmetic when you were little. The fear is what kills most people.
Got my IB Math exam tmr... ive been going through almost all calculus videos now. Ive learned more from this guy on a few hours than 1 year of my teachers teaching..
Screw paying a tutor when there are so many better ones online for free...and most of them make perfect sense and more than my teachers! Thanx for the videos
you calculus videos helped me gain a better understanding of the topic. i seriously can't thank you enough for what you are doing for those such as myself who need help.
dude u rock man keep up the gud work u really doing something dat is very moral. i m in school n i m gonna a give a IIT(really tough all india engineering exam) for which my tutions r charging about half a million Rs so wat u r doin is really helping a lot of ppl who r not dat privileged keep it up
I was bewildered and feared I might fail my Applied Calculus class but since I found your excellent tutorial videos, I am confident I can beat and be one of the 5 scoring students in the class!! And indeed, I wholeheartedly thank you Salman. May Allah bless you with Janatul Fardowsa*
very good absolutely useful too bad i couldnt find this three weeks ago lol hopefully you have something on partial derivatives thats what we are on now in class
dude ur pretty good i like ur style and teaching method. pretty awesome im understanding this better. im from sydney australia and pretty impressed with your work. this is helping me get me into shape for me to understand some complex economic theories.
Very helpful for self-studying calculus! I'll cover the stuff in spivak and in another textbook I found for a dollar, go over problems in each, and refer to these videos to round out that comprehensive study! Thanks!
I like the dy/dx notation because it really means 'change in y divided by change in x', so in a real world problem, when you know the change in x, you can then find the change in y (or visa versa); in other words if you're given a change in x, you can calculate the change in y, just by taking the derivative of the function and multiplying it by the change in x (algebraically). Am i making sense? Great videos, Sal! You're awesome!
In my class we did the same thing but my teacher explained it different. He never explained why He said " We have 4x^5 multiply by the power (5)(4x^5) and reduce power by one (5)(4x^5-1) which is 20x^4" You explain it as "4x^5 = 4 (dy÷dx x^5) = 4 (5x^4) = 20x^4" Your way is so much easier to understand!
Thank you so much... I have a terrible time in school... between ADD, and just a simple lack of desire to learn, I rarely walk away from a course learning anything. However, out of the 30 minute's I've spent watching your videos, I've learned more than this entire semester of college.
...my teacher just needs to keep his mouth shut and show these videos during class..., the man whispers and talks fast....which is why I have to learn from youtube, these videos are a life saver
U DESERVE THE NOBLE PRIZE MORE THAN MR OBAMA. I MEAN LOOK AT THIS GUY HE IS TEACHING SOMEONE IN AMERICA, ME IN MIDDLE EAST AND GOD KNOWS WHERE IS THE OTHER ONE. I JUST WANT TO SAY A BIG THANK YOU
@WarmBread123 ..basically means 'differentiate with respect to x' (since you're only dealing with x then it's just telling you to take the derivative).... soon you might see dy/dx..and that's 'differentiate y with respect to x'
OH MY GOD!!!! THIS HAS BEEN LIKE A WEEK LONG SUMMER PROJECT!!! ALL I WANTED TO DO WAS KNOW HOW PPL FIRST CALCULATED PI AND NOW I'M ADDICTED TO KRACKACADEMY!!! help me :O
Sal, you are a beast. :) I am planning on majoring in math and i was wondering what are some of the hardest math courses in college? Congrats for everything you do. Note: if i were a billionaire, i'd donate millions of millions to your academy and you since you quit your job in 09 :)
@TiredNReclasMusic no the derivitave of 5x would be 5 because 5x^1 so 1 * 5 = 5 so thats the new co-effecient, and the exponent would be suptracted to it would be to the power 0 but thats only to the x. so it would be 5* x^0 = 5*1 = 5.
Okay so known that as H approaches zero it equals f(x)+h-x (squared) divided by h. So then (x+h)(squared)-x (squared) divided by h= The limit as H approches zero which equals 0. So next if you take all that info you can see that is x (squared) +2xh+h (squared) -x (squared) divided by h so simplified it would be (2x+h)= 2x which is the formula for f'(x)=2x :)
x^3 = 3x^2 because you do the power times the constant so 3*x = 3x and then the power you just used which is 3 us decriment it by -1 so 3-1=2 then 2 becomes the new power so final answer is 3x^2
Something seriously wrong with his computer and software. He needs to get it sorted before recording any more videos. It is like a broken record, oh my pen stopped working again, blah blah,,,, come on now, you've got an MS in Engineering after all. What a joke!
+discuss21 Just because he has a degree in Engineering it doesn't mean that he wants to stop the video and fix his pen tool. Also, he might hope that it will eventually stop malfunctioning.
That's the point of the derivation: we are searching the slope of a curse at a specific point, which will be equal to the slope of the *tangent* of the curve at that point. A tangent is a straight line that touches a curve at one and only one point; if you put a (perfect) ball on a table, you can say that the table is tangent to the ball. Calculating the derivative is like putting a ruler on curve and detmining that the slope of the curve at the point of contact = slope of the ruler. Cool?
It's been 8 years and almost 10 months since this video was made... I sincerely hope he's gotten a new pen by now.
He already did. Give it another 8 years and you'll probably be watching Khan Academy in 3D.
+The Family Picture lol
***** You just wait. You'll feel like you can just reach out and touch the polynomials with your fingertip!
lol that's good !
He already got a new pen and everything looks clearer now, I try to avoid his videos with the old pen and try to look for another one about that same topic
Whenever I watch Khanacademy's videos, I feel like the entire universe just makes total sense all of a sudden.
How is it going 8 years later
@@dularar8934 If she was learning this in high school as a freshman (where most people do) she probably has graduated with a master's degree.
@@78anurag freshman in hs taking calculus i or AB, no way.
This is one of the best things to come from the internet (imho) - an altruistic push towards free, quality education available to anyone. Not only that, but the teaching methodology improves over time, so the learnability and retention of material can improve for students of all backgrounds! Loved Sal's TEDTalk on AI and Education, he's a true pioneer.
Better than any textbook and probably most professors that try and teach this subject. Thank you for all that you do!
You needed better textbooks man, try RD dharma Class 11 or HC verma vol 1
This is one of the best channels on TH-cam and I feel so sorry for fellow students who haven't come across it yet. You've made me fall in love with calculus. Thank you
Learned more from this than my entire semester so far.
Mrraaaaggghhh!
Very worrying if this is true. What on earth goes on where you are studying, do you or any teachers do any work there?
It was a russian who could not be understood. I was exaggerating also
Cal is easy, it's all good. (One year later)
Merica how about now
I also want to once again thank Sal, and all the people that make these videos possible. Most of us realize he was the driving force, but other people have contributed aswell. These videos helped me through my precalc course to end with a high B after coming in way behind not knowing alot about algebra. They are now helping me learn physics and the calculus behind the calculations for the equations. Thanks again guys/girls, and special thanks to you sal, for being such a great teacher.
God bless the guy who invented the internet. 😆
Here I am in the middle of the Australian bush learning calculus.
Tim berners lee, invented the internet.
This semester was my hardest math class I'd felt in my life, but after I watched this video!!! You're awesome Salman, You helped me a lot.
This guy should be everyone's teacher, because the learning is supreme to any other :D
Even for me who doesnt have english as a main language!
My teacher looks useless next to this, I would like to thank you for saving my university place for September...I was about to fail calculus. I could not understand a thing, until now.
Thanks so much!
Someone buy this helpful man a bamboo drawing board so he can write in peace.
You sound so happy throughout all of these videos.
Listening to you talking sounds like, "And let's say :D :D x is equal to :D :D :D 4 and :D ..."
Sal, you're a genius. Why can't everyone explain as well as you do? Whenever I'm stuck in my mathbook, I look at your vids and it's just crystal clear. Thank you :)
So many comments of thanks, but I feel the need to add mine as well.
Many thanks for taking your time to spread free education, especially on such a vast scale. It is truly a marking point in the evolution of man when learning becomes viral. It truly marks a point in the evolution of man, as we approach perfection. What an honor Mr Khan.
Not sure why everyone's guffawing over the "I'm 15 years old" comment. It's not hard to watch a video on TH-cam when you're 15. As long as you're not intimidated by the idea of calculus, learning it from Khanacademy isn't any harder than learning arithmetic when you were little. The fear is what kills most people.
but im 9 years. old
I'm just trying to learn ahead, but I gotta say this: You are amazing. Keep up the good work.
sir God bless you ❤
Got my IB Math exam tmr... ive been going through almost all calculus videos now. Ive learned more from this guy on a few hours than 1 year of my teachers teaching..
Thank you so much for helping me in conceptualising things. You do save me a lot of time. Thanks!!
Greatest teaching quote ever: "the more examples we do, the better."
Screw paying a tutor when there are so many better ones online for free...and most of them make perfect sense and more than my teachers! Thanx for the videos
Never thought I'd think this, but calculus is fun. (*_*).
It Sure is!!
you calculus videos helped me gain a better understanding of the topic. i seriously can't thank you enough for what you are doing for those such as myself who need help.
dude u rock man keep up the gud work u really doing something dat is very moral. i m in school n i m gonna a give a IIT(really tough all india engineering exam) for which my tutions r charging about half a million Rs so wat u r doin is really helping a lot of ppl who r not dat privileged keep it up
Thank you, thank you, thank you so much, your videos had been such a great help! Thank you!!!❤️❤️❤️
It's 16 year now. 🎉🎉🎉
I was bewildered and feared I might fail my Applied Calculus class but since I found your excellent tutorial videos, I am confident I can beat and be one of the 5 scoring students in the class!! And indeed, I wholeheartedly thank you Salman. May Allah bless you with Janatul Fardowsa*
you are a lifesaver! I wish all teachers were capable of teaching like this
very good absolutely useful too bad i couldnt find this three weeks ago lol hopefully you have something on partial derivatives thats what we are on now in class
dude ur pretty good i like ur style and teaching method. pretty awesome im understanding this better. im from sydney australia and pretty impressed with your work. this is helping me get me into shape for me to understand some complex economic theories.
This man is a legend he is saving me from failing my calc quiz 12 years later :)
Very helpful for self-studying calculus! I'll cover the stuff in spivak and in another textbook I found for a dollar, go over problems in each, and refer to these videos to round out that comprehensive study! Thanks!
I like the dy/dx notation because it really means 'change in y divided by change in x', so in a real world problem, when you know the change in x, you can then find the change in y (or visa versa); in other words if you're given a change in x, you can calculate the change in y, just by taking the derivative of the function and multiplying it by the change in x (algebraically). Am i making sense? Great videos, Sal! You're awesome!
This makes so much more sense than what my teacher taught me 🙏🏼
salman, this is gr8... I wish we had better teachers in school..I had to rote learn all the formulae..
you're amazing! thank you so much for all you do!
you're sooo much better than my teacher! i didn't know what i was doing until i watched your videos! muchos gracias!!
In my class we did the same thing but my teacher explained it different. He never explained why
He said " We have 4x^5 multiply by the power (5)(4x^5) and reduce power by one (5)(4x^5-1) which is 20x^4"
You explain it as "4x^5 = 4 (dy÷dx x^5) = 4 (5x^4) = 20x^4"
Your way is so much easier to understand!
Thank you so much... I have a terrible time in school... between ADD, and just a simple lack of desire to learn, I rarely walk away from a course learning anything. However, out of the 30 minute's I've spent watching your videos, I've learned more than this entire semester of college.
Its crucial to master the arithmetics of derivatives.
Thank so much for bringing us this great tutorial !
These videos are AMAZING! Khan Academy is a blessing!
Simply fantastic, thank you
...my teacher just needs to keep his mouth shut and show these videos during class..., the man whispers and talks fast....which is why I have to learn from youtube, these videos are a life saver
Thanks for the excellent teaching. These videos are crystal clear, and very easy to understand.
Students : 1
Guy calling on the cell phone : 0
Wow, watching these videos made calculus sound 100 times easier. Thanks.
fighting a massive headache and studying for calc exam tomorrow, these are coming in massively handy. (Thank you) ^ ∞
thank u , u are such an inspirational teacher, now because of you i found out that this stuff is easyyyyyyy, thx :)))
omg! thank you thank you thank you! finally...someone just being plain about it! geez!
i love your videos. thank u so much. your helping me get thru college!
U DESERVE THE NOBLE PRIZE MORE THAN MR OBAMA. I MEAN LOOK AT THIS GUY HE IS TEACHING SOMEONE IN AMERICA, ME IN MIDDLE EAST AND GOD KNOWS WHERE IS THE OTHER ONE. I JUST WANT TO SAY A BIG THANK YOU
I am SO HAPPY that you help me every day understand math concepts that my proffessor tries to explain... I would fail my semester without your videos.
Now, whenever I'll study Derivatives I'll think about the malfunctioning pen which drove Sal crazy
Nice video which help me a lot.
Thank you so much again for this... you make it so easy to understand it !
@WarmBread123 ..basically means 'differentiate with respect to x' (since you're only dealing with x then it's just telling you to take the derivative).... soon you might see dy/dx..and that's 'differentiate y with respect to x'
awesome my friend...all of us....really enjoy your videos...from lima peru
This is the best academy ever! Ever!
this is way better than my teacher, wow....cant thank you enough
im in grade 12 and this will help me alot this year. Thankyou very much!!!
OH MY GOD!!!! THIS HAS BEEN LIKE A WEEK LONG SUMMER PROJECT!!!
ALL I WANTED TO DO WAS KNOW HOW PPL FIRST CALCULATED PI AND NOW I'M ADDICTED TO KRACKACADEMY!!!
help me :O
Math is FINALLY starting to make some sense!
Sal, you are a beast. :) I am planning on majoring in math and i was wondering what are some of the hardest math courses in college? Congrats for everything you do. Note: if i were a billionaire, i'd donate millions of millions to your academy and you since you quit your job in 09 :)
Thumbs up for this guy helping us in college!
classes aren't going to let you use that polynomial derivative shortcut.. was hoping i could get real prac! :)
Very Helpful. Thank you.
you give me so much confidence. thank you!
@TiredNReclasMusic
no the derivitave of 5x would be 5 because 5x^1 so 1 * 5 = 5 so thats the new co-effecient, and the exponent would be suptracted to it would be to the power 0 but thats only to the x. so it would be 5* x^0 = 5*1 = 5.
You are a skilled teacher! This has made my class much more understandable, I prefer you to my professor :p
Only if I could have you as my professor. My day will be a lot more easier and less stressful!
I love you for this video
I guess, 14 years ago it was a big deal to even have the technology to manually write on a device.
Incredible... Smile all over my face!
you are the best, sal!!! i finally get it.
Okay so known that as H approaches zero it equals f(x)+h-x (squared) divided by h. So then (x+h)(squared)-x (squared) divided by h= The limit as H approches zero which equals 0. So next if you take all that info you can see that is x (squared) +2xh+h (squared) -x (squared) divided by h so simplified it would be (2x+h)= 2x which is the formula for f'(x)=2x :)
Feels so great to unlearn and relearn calculus now after so long (may be 14yrs) :D
I'm studying slightly ahead, because your videos are so fluid. thank you.
Yeah me too
I am 9th grade so yeah guess I am ahead
This video was really helpful. Keep making awesome videos like these.
You are an angel!!
thanx for video series
he has more videos that can give you real practice.
x^3 = 3x^2 because you do the power times the constant so 3*x = 3x and then the power you just used which is 3 us decriment it by -1 so 3-1=2 then 2 becomes the new power so final answer is 3x^2
tysm man saving lives.
You made this so easy.
That was helpful no more difference quotient
i love your videos..it makes me happy and satisfy..:)
Thnx man ur a life saver
i love this guy!
Pay hundreds of thousands to institutions and get confused trying to understand what a guy on youtube made seem like a recipe for pancakes...
@iamtheplauge That happens a lot in my class. At least with computers and online videos you can go back and correct mistakes...
... I love the side commentaries about the pen.
He never gets a new pen tool, does he?
Something seriously wrong with his computer and software. He needs to get it sorted before recording any more videos. It is like a broken record, oh my pen stopped working again, blah blah,,,, come on now, you've got an MS in Engineering after all. What a joke!
discuss21
You really don't know who he has become since,eh? Check out khanacademy.com
Kyle Marrotte It was uploaded in 2007.
+discuss21
Just because he has a degree in Engineering it doesn't mean that he wants to stop the video and fix his pen tool.
Also, he might hope that it will eventually stop malfunctioning.
omg u made derivatives fun
That's the point of the derivation: we are searching the slope of a curse at a specific point, which will be equal to the slope of the *tangent* of the curve at that point.
A tangent is a straight line that touches a curve at one and only one point; if you put a (perfect) ball on a table, you can say that the table is tangent to the ball. Calculating the derivative is like putting a ruler on curve and detmining that the slope of the curve at the point of contact = slope of the ruler.
Cool?
Thank you so much sir
Yeah, yeah, thanks Khan.
easy way to know the derivative of simple functions like that are: n X ^n-1 where "n" is the variable of X
Who is watching this in 2021 and wanna prepare for jee
Somebody get this honorable man a good pen
im sure that he has one now that it has been 15 years lol
thank you helped me alot