Linear Algebra 10 | Cross Product

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  • เผยแพร่เมื่อ 21 พ.ย. 2024

ความคิดเห็น • 23

  • @bikespike4150
    @bikespike4150 ปีที่แล้ว +3

    By far one of the best Math channels (and in my opinion recourses in general) out there. Thank you for your efforts. Keep it up

  • @Hold_it
    @Hold_it 2 ปีที่แล้ว

    Oooh, now it makes finally sense why the length gives us the area of the Parallelogramm.
    I just got told that it works, but i didn't see why it makes sense geometrically. The connection was so random for me.
    Thank you!

  • @malawigw
    @malawigw 2 ปีที่แล้ว +4

    I will cross my fingers for this video

  • @paominlienguite2397
    @paominlienguite2397 2 ปีที่แล้ว +1

    My favourite channel 😍😍😍

  • @andrewxiwu
    @andrewxiwu 2 ปีที่แล้ว +1

    As a way to remember this, wouldn't it be nice to point out that component 1 is the determinant of row2+row3? (and similar for other components) :). Of course, this determinant thing will happen again and again in later studies

    • @brightsideofmaths
      @brightsideofmaths  2 ปีที่แล้ว +2

      Of course, the determinant we will cover soon :)

    • @rafaelschipiura9865
      @rafaelschipiura9865 ปีที่แล้ว

      I don't like this way of explaining it because it makes it look like the cross product can be extended to R^n with n different from 3.

  • @thiloherold7087
    @thiloherold7087 2 ปีที่แล้ว +2

    Hi,
    As always a brilliant video! But one question arises while watching, why does this only work in R^3? In other words: what makes this space so different from R^2, R^4 or R^42?
    Thank you in advance!

    • @brightsideofmaths
      @brightsideofmaths  2 ปีที่แล้ว +1

      We can discuss this in more detail later. However, the orthogonality property cannot be true in R^2 or R^4 as you maybe can visualize.

    • @nathanwycoff4627
      @nathanwycoff4627 2 ปีที่แล้ว

      @@brightsideofmaths I would just like to second this question; I'm also super curious if there are higher dimensional analogues :)

    • @brightsideofmaths
      @brightsideofmaths  2 ปีที่แล้ว +2

      @@nathanwycoff4627 Yeah, there are but not as a product with two factors like here. We will discuss it later :)

    • @thegoofiestgoooberr
      @thegoofiestgoooberr ปีที่แล้ว

      @@nathanwycoff4627the only analogue i know of is in 7 dimensions

  • @ChrisOffner
    @ChrisOffner 2 ปีที่แล้ว

    The one thing that every single video on the cross product, including this one, seems to omit, is how to connect the algebraic formula/definition to a geometric intuition, i.e. *why* (in a geometric sense) does this algebraic definition result in a vector that's perpendicular to *u* and *v* and whose length matches the area of the parallelogram?
    The same goes for introductions of the determinant: *Why* (in a geometric sense) does the algebraic definition of the determinant of a matrix M give us the volume of the paralellepiped to which which the unit hypercube is mapped by the linear map encoded in M?

    • @brightsideofmaths
      @brightsideofmaths  2 ปีที่แล้ว +1

      True! I want to cover this in general when we talk about the determinant. However, it felt wrong not to define the cross product early.

    • @ChrisOffner
      @ChrisOffner 2 ปีที่แล้ว

      @@brightsideofmaths Would be wonderful if you could cover it! Thank you, I greatly enjoy your videos. :)

    • @brightsideofmaths
      @brightsideofmaths  2 ปีที่แล้ว +1

      @@ChrisOffner I have already some videos about the determinant in German. However, the English ones will be even better because it's embedded in the whole Linear Algebra series then :)

    • @Hold_it
      @Hold_it 2 ปีที่แล้ว

      @@brightsideofmaths Oh, that would be great. I always wondered why the cross product works :)

  • @Independent_Man3
    @Independent_Man3 2 ปีที่แล้ว +1

    Hello, I live in a slightly noisy environment. Can you please increase your mic volume in future videos? I like watching your videos.

    • @brightsideofmaths
      @brightsideofmaths  2 ปีที่แล้ว

      This is something TH-cam should do automatically. Is it much quieter than other videos?

    • @Independent_Man3
      @Independent_Man3 2 ปีที่แล้ว

      @@brightsideofmaths Right after your video, I watched this video th-cam.com/video/VCHFCXgYdvY/w-d-xo.html and the sound was much louder. Just to give an example.
      If you can make it louder without much effort, then great. Otherwise, no problem.

    • @brightsideofmaths
      @brightsideofmaths  2 ปีที่แล้ว

      @@Independent_Man3 I cannot reproduce this effect. Sorry. Maybe you try another browser?

    • @brightsideofmaths
      @brightsideofmaths  2 ปีที่แล้ว

      @@Independent_Man3 Yeah, both videos have exactly the same loudness for my computer.

    • @notu483
      @notu483 ปีที่แล้ว

      It is possible to turn on the captions to read the text rather than listening to it. This is a useful tool to watch these videos even within a noisy environment.