Identifying circles and parabolas from equations | Conic sections | Algebra II | Khan Academy

แชร์
ฝัง
  • เผยแพร่เมื่อ 16 พ.ย. 2024

ความคิดเห็น • 32

  • @MrKiromunist
    @MrKiromunist 14 ปีที่แล้ว +3

    @LancerZEV Yeah that's right !
    Sal wrote
    0 = -2x²-12x-16
    0 = -2(x+6x+8)
    But the second line should be "0 = -2(x²+6x+8)"

  • @sheff583
    @sheff583 13 ปีที่แล้ว +1

    You sir are a king amongst men and i am now passing my summer algebra and therefore able to go to Amsterdam. i salute you.

  • @gman71878
    @gman71878 12 ปีที่แล้ว +1

    Dude words cant even describe how much you helped me. I understand all this now. Thanks a bunch.

  • @TheJstfilms
    @TheJstfilms 11 ปีที่แล้ว +2

    I worship this channel

  • @brendareyes3207
    @brendareyes3207 9 ปีที่แล้ว

    so..I'm a major procrasinator and math is not my thing and this just makes it ten times easier!! love this channel

  • @futurelizp
    @futurelizp 14 ปีที่แล้ว

    Thank you Sal. I couldn't understand it from the books. Now I do. Thank you.

  • @espen180
    @espen180 15 ปีที่แล้ว

    if you change the x-terms to r-terms, for radius, you should get the 3D-analogs of the 2d conic sections. The r-term then stands for the radius of the 2D cross-section of the object in the y-normal-plane.
    For example, the equation for a sphere is y^2+r^2=R^2, where R is the radius of the sphere.

  • @elementoxygen
    @elementoxygen 15 ปีที่แล้ว +1

    You mean, in a 3D world, not i a 3D world.
    But Sal, that was a great vid!

  • @zXThatNinjaXz
    @zXThatNinjaXz 11 ปีที่แล้ว +3

    I'm in AP Calculus in high school, trying to tutor my girlfriend, and I am still having trouble comprehending this, lol.

  • @idster7
    @idster7 15 ปีที่แล้ว

    where is the next section where conics theory & how they came about is talked about??

  • @GenericCoder
    @GenericCoder 13 ปีที่แล้ว +1

    Great video sal,but in 6:56 there is a slight mistake though in writing it didn't appear as -2 it appeared as though.

  • @seanfleetham6733
    @seanfleetham6733 8 ปีที่แล้ว

    Your a good pal sal. Thanks for the help!

  • @Mathview
    @Mathview 15 ปีที่แล้ว

    Nice presentation. Thanks for posting.

  • @StevenZB1
    @StevenZB1 15 ปีที่แล้ว

    Go on his TH-cam page and on the top it has a donate button you can click on.

  • @tropicalmist999
    @tropicalmist999 15 ปีที่แล้ว

    i have checked but nothing as good as Khan could explain, I wonder if he does do LSAT logic, I don't see why he wouldn't- How could i ask him, i'v emailed and comment numerous times but i get no response

  • @fleshcookie
    @fleshcookie 13 ปีที่แล้ว +2

    I believe there is a mistake in this video. at 6:32 when he factors out a -2, if you were to distribute that negative 2 back into (x+6x+8) you would get -2x -12x -16. NOT -2xSQUARED -12x -16. Unless i am missing something critical can someone please explain to me why that is happening?

  • @tropicalmist999
    @tropicalmist999 15 ปีที่แล้ว

    Do you do LSAT logic; really want to know! Answer ur comments KHan! lol Excellent video as always. You should be paid for this. Can i donate? if so where?

  • @dikoknows7234
    @dikoknows7234 5 ปีที่แล้ว

    What is the conic section of equitation is this? Please help
    3x²+6x+4y=18
    ??

  • @tropicalmist999
    @tropicalmist999 15 ปีที่แล้ว

    oh ok thanks i see it now, do you know if khan does LSAT logic?

  • @NikhilThomasJoy
    @NikhilThomasJoy 14 ปีที่แล้ว

    how will you do this?
    9x2-130x+16y2-160y-24xy+125=0

  • @norwayte
    @norwayte 15 ปีที่แล้ว

    Conics in 3D would be interesting too. Because we live i a 3D world.

  • @lucidfangirl1030
    @lucidfangirl1030 3 ปีที่แล้ว

    2:47 I'm confused. Why is it (y+2)^2? Wasn't it just 4y/2= 2, so (y-k)^2?

  • @DarklightALBANIA
    @DarklightALBANIA 13 ปีที่แล้ว

    @fleshcookie He forgot to write it but he didn't forget it in his head so the rest of the equation is solved correct

  • @StevenZB1
    @StevenZB1 15 ปีที่แล้ว

    I don't think so but I'm sure it's somewhere else on TH-cam.

  • @sesshysayoyasha93
    @sesshysayoyasha93 9 ปีที่แล้ว

    Thanks a lot Sal! This was really helpful!
    However, it is kinda hard that the title is in Spanish but there were no Spanish subtitles available :/.

  • @plumPB
    @plumPB 7 ปีที่แล้ว

    would you tell me which is the software?

  • @knowledgepower7286
    @knowledgepower7286 9 ปีที่แล้ว

    Khanic Identification 3 COLD

  • @SathvickSatish
    @SathvickSatish 7 ปีที่แล้ว

    Why should it always equal zero? The x and y

  • @knowledgepower7286
    @knowledgepower7286 9 ปีที่แล้ว

    Filip Shumilo I feel ya

  • @idster7
    @idster7 15 ปีที่แล้ว

    @tropicalmist999 he's probably gotten thousands of emails so it's tough for him to reply.

  • @jmm00702
    @jmm00702 14 ปีที่แล้ว

    ur fucking awesome