Infinite limits intro | Limits and continuity | AP Calculus AB | Khan Academy

Here we consider the limit of the function f(x)=1/x as x approaches 0, and as x approaches infinity. Created by Sal Khan.

AP Calculus AB on Khan Academy: Bill Scott uses Khan Academy to teach AP Calculus at Phillips Academy in Andover, Massachusetts, and heÕs part of the teaching team that helped develop Khan AcademyÕs AP lessons. Phillips Academy was one of the first schools to teach AP nearly 60 years ago.

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[whysomad]

IT'S THIS EASY? Whats all the bs on other sites about dividing by the highest power in the denominator then? HOLY FRICK I LOVE KHAN ACADEMY

[noemihersheyi.alvero]

Khan Academy Has been there for me since I was in 8th grade. *Its like listening to Dwayne Johnson teaching me Math* 😂😂😂Its really fun, entertaining and prevents me from procrastinating.

[ohh]

where have you been ALL of my life.. I really would have paid attention in class back then seeing something like this back then<3

[vuyolwethumekeni]

it's very easy than I expected Thank Khan Academy... LIKE YOU REALLY

[PrasannaKumar-zxgr]

Thanks sir... My book confused me a lot... But you made me to understand well.. And now I can confidantly read my book

[Gourmeticainsularis]

(cont.) I am currently finished with exponential functions, growth, decay, and that bacteria problem, ready to move on. Learning from you has been very enriching so far, again I thank you. After trig i'll move onto calculus and probably finish that by the end of summer, and will be able to learn physics from the master. It's also great that you guys have these videos in over a dozen videos. The majority of 7 billion people can understand your videos. that's just great.

[Gourmeticainsularis]

Sal I really, really appreciate what you guys are doing at Khan Academy. I'm a sophomore in high school taking geometry and chemistry, but I want to read the Feynman Lectures on Physics, requiring some knowledge of calculus. By perusing your videos on calculus, it is evident I need to learn trigonometry to learn calculus. So I have to learn trig to learn calculus to fully undersand feynman's beautiful explanations of physics, and you guys are making that so much easier, and more fun. I thank you

[Kenchan]

best describtion i've heard for infinity so far is that it's a word we use when we don't know.

[domgluhwein]

Thanks man! I finally understood the concept :D

[Mmmmaxman]

f of x would be approaching 1/infinity so in a sense f of x would be approaching 0, but it is impossible to reach it, it is like halving the distance between 2 points infinitely the distance would never reach zero, but it would continually get smaller and smaller, this is the same concept that is used to explain the function f of x approaching infinity because infinity is not finite, so nothing can reach it.

[jdsol]

does the concept of infinity include the entirety

[PeterGeras]

What you're talking about are infinitesimals, and they don't exist in the real numbers, but there is a number system that does include them, which is the extended real number line - but this number system isn't the conventional one that we use.
The problem with saying that x= 1/inf is because infinity doesn't exist in the real number line either, which is why we have limits to get over this hurdle.

[Mmmmaxman]

It isnt the same as zero, but it is commonly approximated to zero because it is infinitely close to zero like 10x10 to the negitive infinite, it is infinitely close to 0 but will never at any point be zero

[avarussurava]

the whole thing was like travelling to africa but arriving in antartica, quite complicated to uunderstand but with more than 2 plays I guess i'll understand, thanks math genius ! ;))

[Hakkim]

Please upload videos for Dravidian i.e தமிழர்கள் in Tamil for better understanding

[RealStrategyGaming]

1/0 can be anywhere a straight line up and down. So which 0 of the infinity are we talking about can be anything..

[rohitramaswamy]

lets just say i have a log function and the closer y gets to 5, y will increase by a lot and when y is 5, x is infinity. How do I graph that in excel

[Nikifuj]

Division is an elementary algebra thing you do to real numbers, and infinity isn't a real number. Intuitively you could think of it that way, but that's not exactly rigorous (unless you read some nonstandard analysis books).

[PeterGeras]

No, it can't. You're thinking of the indeterminate form 0/0. 1/0 is undefined in the sense that it's +inf and -inf simultaneously. It's not any number of finite values though.

[Tobi-lshx]

This says its for AP Calculus, but Im in Algebra 2? I need to understand this