Multivariable Calculus: Distance from a point to a plane

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  • Опубліковано 18 гру 2024

КОМЕНТАРІ • 17

  • @punditgi
    @punditgi Рік тому +1

    Excellent video! 😊

  • @Ringingbloom_j
    @Ringingbloom_j 3 місяці тому +1

    Thank you!!

  • @mmd8075
    @mmd8075 Рік тому +1

    Hi, if we have more teachers like you, math would be accepted easier. My university math professor tells us "memory this and that", i cant im sorry. hahah

  • @thomashowe1920
    @thomashowe1920 Рік тому +1

    Honestly, it took me a couple of minutes to see that one does not need to find the point where “l” and the plane intersect. Thanks for the insight.

    • @bevinmaultsby
      @bevinmaultsby  Рік тому

      You’re welcome! You can also find that point if you’d like, there are often multiple ways to proceed.

  • @sethsherman-ek4po
    @sethsherman-ek4po 8 місяців тому

    Hey there. For some reason, I can no longer find your Cal 4 series of videos. Am I overlooking something, or are they no longer available? Thank you!

    • @bevinmaultsby
      @bevinmaultsby  8 місяців тому

      Gosh, I hope not! I think all my playlists are still here: www.youtube.com/@bevinmaultsby/playlists
      I don't have anything called Calc 4, you might be looking for Calc 3? ua-cam.com/play/PLBEl4BT8wUgOqJCBijQxClMIuumgtMinc.html&feature=shared

  • @mmd8075
    @mmd8075 Рік тому

    My approach was we have point (1,2,3) and we have normal vector (3,-1,5) so i did this line (x,y,z)=(1,2,3)+k(3,-1,5) intersected with the plane then calculated the distance between points.

    • @bevinmaultsby
      @bevinmaultsby  Рік тому +1

      Perfect! That would land right on that point I sketched at the beginning.

    • @mmd8075
      @mmd8075 Рік тому

      @@bevinmaultsby but your approach shows us there are many more approaches and something we forget is we can find many points in a plane and a line.

  • @jackflash8756
    @jackflash8756 Місяць тому

    It isn't clear to me how you made the assumption that vector n had coordinates 3, -1, 5 . If you are using some 3D coordinate reference system , the coordinates 3, -1 , 5 is just a point on the plane , not a vector. To determine vector n , surely one would need the coordinates of the tip end of vector n as well as the coordinates of its tail end (which is 3,-1,5). Further , sq root 35 x sq root 35 = 35

    • @bevinmaultsby
      @bevinmaultsby  Місяць тому

      Hi Jack, when a plane has the general form ax + by + cz = d, then the vector (a,b,c) is perpendicular to the plane -- in this case, the vector (3,-1,5). That is not a point on the plane (notice it does not make the plane equation true). Remember that vectors do not live in prescribed places in space--the vector which begins at the origin and goes to the point (3,-1,5) is the vector (3,-1,5), but you can slide it around in space wherever you'd like. So I can slide that vector into the position where I sketched it on the diagram. For your last remark, when I broke the projection into v.n/||n|| * n/||n||, the idea was that the length of that (which is what we want) is | v.n/||n|| * n/||n|| | = | v.n/||n|| | (because n/||n|| has unit length). Therefore, there is only one copy of sqrt(35) in the denominator, as the other one was used to normalize n.

  • @sethsherman-ek4po
    @sethsherman-ek4po 8 місяців тому

    Sorry for bothering you, then. I thought I remembered seeing it before I left Africa. Probably just wishful thinking.