Washer method rotating around vertical line (not y-axis), part 1 | AP Calculus AB | Khan Academy

[@guinthehouse]

For anyone curious this is used in calculus 2 for college level lol

[@itsrainingafterall]

can confirm

[@spidermand100]

His drawing skills have definitely improved from the early integral videos.

[@muhdkhairulamirinum3985]

thank you sir

[@cursodedibujo-maritoaranda2980]

You can see it like: phi is for the 180º degrees, the semicircle; and square is for the simetry that covers the other negative side of the axes. That's one way to picture it

[@iLBZ1]

THANK YOU. SO. MUCH!

[@chonylau6981]

Thanks!!!!

[@davidlancaster5804]

Way better than my college math teachers!

[@MoFo5869]

what would happen if you rotate around a negative vertical line, (x=-2, would it be 2+y^2)?

[@saml5902]

Absolutely

[@podojeff4797]

Bruh I’m struggling so hard in Ap calc and my exam is literally in like a month and a half or so 💀

[@kiwi9660]

whatd you get on the exam

[@podojeff4797]

@@kiwi9660 a 2 😁🔫

[@kiwi9660]

@@podojeff4797 oh crap

[@SethuIyer95]

Most useful video

[@mrmansir3734]

at 7:34, is there another way to get the integral numbers (2 and 0) without visually looking at a graph? Graphing it can take a little long during an exam.

[@smartiee]

Yes you can equal the two functions with each other and then find the values of y

[@anderswallmark9787]

I can't find the next video but I got the answer to be pi(191/30). Roughly 6.4*pi area units, a bit much perhaps?

[@CYC10N3_Gaming]

So is the outside radius always the function farthest away from the axis of revolution?

[@dc-nw8kv]

what about if the axis is on the negative side? would it then be y^2-2 and sqrt(y)-2 or would it still be the same

[@milesb1763]

add the distance between y-axis and x=line. Basically, you're moving the functions to be revolving around y=0.

[@mochiman911]

was the answer 31/30 pi?

[@07logiebear]

this is first year calculus for courses like engineering (im doin chem eng)

[@ClayIsBae]

hope u failed out u nerd

[@mariogabrielarandacajide5857]

nobody cares

[@tyriqcleo5899]

Got a job yet? I'm first year now

[@CANOOB18]

I'm watching this as a first year Ivy League engineering student, I don't know if engineering is my future if I already need to watch Khan's vids -_-

[@adamhill2212]

+Fiasco Even engineers have trouble understanding hard concepts. Don't get discouraged, we all learn differently.

[@MossadDid911]

what college?

[@CANOOB18]

General Ouki Cornell.

[@ClayIsBae]

haha take L O S S

[@rezanajdi6165]

I’m doing this in high school and no longer have motivation I have 30 days of school left 😢

[@CarlosFlores-cj2ci]

where's the next video

[@bobbychan2518]

I learned this for Calculus AP which is technically a highschool course. Otherwise I believe its a first year Calculus material.

[@seanscientific1035]

where is the other half of y = x^2????

[@FailLegitly]

does anyone know how to do this with respect to x? (using dx instead of dy)?

[@joeseppy69]

Matthew Tran not sure if there is a way because you’re rotating it around a vertical line, meaning you’ll need to find the area between the function and the vertical line with respect to y.

[@joeseppy69]

Actually never mind, you can by using the shell method.

[@thekarsynrae]

The answer is 31pi/30 by the way

[@blobfishlover7667]

Wait, why isn't the outer radius 2-sqrt(y) and the inner radius 2-y^2?

[@michaelmunoz3736]

Because the outer radius corresponds to the function furthest from what your revolving around

[@yukiihiro8368]

I think the answer is 61pi/30

[@dulara5448]

kzbin.info/www/bejne/n161k2eVo55lb80 Part 2 of this

[@Igio77]

Oh snap, I messed this up Now I have -10 p on my test :S

[@saadrehman362]

what did you get overall?

[@river8477]

I'm sorry I disagree heavily. That is not orange that is salmon pink

[@anupriyakumari2592]

Was that important to make the explanation so messy and confusing...