Language and notation of the circle | Introduction to Euclidean geometry | Geometry | Khan Academy

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  • เผยแพร่เมื่อ 5 ก.พ. 2025
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    Formal definition of a circle. Tangent and secant lines. Diameters and radii. major and minor arcs
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ความคิดเห็น • 70

  • @lilleepoindexter3991
    @lilleepoindexter3991 ปีที่แล้ว +2

    I love khan academy they just seem to use IRL saings like that one really cool teacher

  • @nightmarewow9658
    @nightmarewow9658 4 ปีที่แล้ว +5

    1:43 "this is a CIRCLE" POG

  • @slimatix1970
    @slimatix1970 4 ปีที่แล้ว +11

    this is my assignment to watch this vid

    • @rainbow8213
      @rainbow8213 4 ปีที่แล้ว

      JENNA E ELLIS same.

  • @technostar2655
    @technostar2655 3 ปีที่แล้ว +2

    I like your videos very much because the explanation are so nice and understanding

  • @Aadiweb
    @Aadiweb ปีที่แล้ว

    0:28 its 4.5 now in fullscreen

  • @xiaoranfan9804
    @xiaoranfan9804 7 หลายเดือนก่อน

    2:14 720 cm total

  • @KornIndulgence
    @KornIndulgence 12 ปีที่แล้ว +1

    This helped so much!You're not boring like some of these help videos on here.

  • @nickpower1837
    @nickpower1837 10 หลายเดือนก่อน

    10:40 if TK was a diameter, what would be the major and minor arcs of TK?

  • @Volti9
    @Volti9 6 ปีที่แล้ว +2

    Los subtitulos en español dejan de aparecer en el minuto 4:10 :(

  • @chau4444
    @chau4444 8 หลายเดือนก่อน

    Very useful!

  • @TeuhidChannel
    @TeuhidChannel 13 ปีที่แล้ว

    this is soo good!!and the handwriting is very nice

  • @yodashortlikeme
    @yodashortlikeme 12 ปีที่แล้ว +1

    What if there are no specified points between the points of a major arc? how do we write a major arc differently than a minor arc?

  • @Aadiweb
    @Aadiweb ปีที่แล้ว

    0:28 thats exact 3 centimeter on my screen bro

  • @jerfersonmatos28
    @jerfersonmatos28 7 ปีที่แล้ว

    For those who ask which program he uses to draw, you can just use paint. Just take the ink tin and set the screen to black, and to draw don't use the pencil tool, use the brush tool

  • @joshr8466
    @joshr8466 10 ปีที่แล้ว

    should line l (L, not 1, if that wasn't clear) have arrows on both sides? In the video, it doesn't have arrows, and I'm wondering if that's correct.

    • @rafaelsanzio8734
      @rafaelsanzio8734 7 ปีที่แล้ว

      It is s Just a diferent notation.
      The L is saying thatg is a line..and a line goes on...
      The other notation is with the arrows...
      both are correct...

    • @nickpower1837
      @nickpower1837 10 หลายเดือนก่อน

      i think as long as he doesnt specify any verticies then its just assumed as a line but yes using arrows is more correct

  • @lil00tony
    @lil00tony 12 ปีที่แล้ว +2

    I was a genius, but then I became lazy, so I wasn't as smart as usual. This helps me get to my genius status again, thank you.

    • @clodgozon3968
      @clodgozon3968 5 ปีที่แล้ว +4

      I'm skeptical about that. It's not that I'm saying that you are lying. Many people would just say the same thing. Most smart people wouldn't say such thing to themselves, because they still have still a lot of things to learn for.

    • @amalldekan1432
      @amalldekan1432 4 ปีที่แล้ว

      @@clodgozon3968 Preach!

    • @Methodman2999
      @Methodman2999 3 ปีที่แล้ว

      Don’t call yourself a genius, so easily. it’s not that I doubt you or anything, but it sounds pretty egotistical to call yourself a genius if your really a genius do a iq test, and if you get above a 140 your a genius

    • @abxsmal
      @abxsmal 3 ปีที่แล้ว

      @@Methodman2999 iq tests dont say anything.

    • @Methodman2999
      @Methodman2999 3 ปีที่แล้ว

      @@abxsmal yea but it’s one of the only ways to know if your a genius or not also if you have a iq above 140 your almost guaranteed to be genius so I would say it does say something

  • @Kashif_Javaid
    @Kashif_Javaid 13 ปีที่แล้ว +1

    Hi sal, how come you are not using circle tool to draw circle?

  • @robinfan1488
    @robinfan1488 11 ปีที่แล้ว +1

    It is radii and dont ask me why its spelled like this i dont know maybe cause the people who thought of this spelling are weird

    • @viruzz505
      @viruzz505 5 ปีที่แล้ว +1

      Ik it’s been 5 years, but singular words that end in -us end in -i as plural.
      For example, fungus is singular, fungi is plural.

  • @Beverly1340
    @Beverly1340 13 ปีที่แล้ว

    IS THIS SUPPOSED TO BE BEGINNERS GEOMETRY? WHO DOES THIS BESIDES A GENIUS?

    • @bostonpatriot613
      @bostonpatriot613 7 ปีที่แล้ว

      Start from lesson 1, which is about Euclid. The second lesson is about lines. The third is about angles; then we get to this segment. You'll get it, I hope, and not think you have to be a genius to understand. (There is a type of dyslexia, however, for whom points and lines representing anything will be meaningless. They learn in another way.)

    • @clodgozon3968
      @clodgozon3968 5 ปีที่แล้ว

      Those were only terms. It ain't problem-solving yet.

    • @Wthebusman
      @Wthebusman ปีที่แล้ว

      This is so easy bud this is words from a 7th grader take it from me

  • @mathgang1
    @mathgang1 12 ปีที่แล้ว

    you can find those at youtube edu

  • @jennifersiagian
    @jennifersiagian 8 ปีที่แล้ว

    Angels are Angles

  • @bootleggreenthanos5944
    @bootleggreenthanos5944 5 ปีที่แล้ว +1

    Bottom Text

  • @Lemonzest96
    @Lemonzest96 7 ปีที่แล้ว

    oh my god, at 9:31 the points form a star. Boom pentagram

  • @theSpicyHam
    @theSpicyHam 13 ปีที่แล้ว

    Note: the secant here is not the sine/cosine/tangent stuff

  • @bootleggreenthanos5944
    @bootleggreenthanos5944 5 ปีที่แล้ว

    Top Text

  • @crazecream241
    @crazecream241 7 ปีที่แล้ว +1

    is chord what you call a line segment in a circle?

    • @rafaelsanzio8734
      @rafaelsanzio8734 7 ปีที่แล้ว

      I guess you are right...straight line that connects two points on a circle.

  • @Hippoman141
    @Hippoman141 13 ปีที่แล้ว

    @SpoiledLogic this comment has helped a lot. Things make sense now :D

  • @kcottonable
    @kcottonable 6 ปีที่แล้ว

    So basically the “Tangent” is in reference to a non-centered point of the circle?

    • @kcottonable
      @kcottonable 6 ปีที่แล้ว

      Hmm...I’ve never heard of a secant line! Another name?

    • @maybeluca8027
      @maybeluca8027 4 ปีที่แล้ว

      @@kcottonable no

    • @maybeluca8027
      @maybeluca8027 4 ปีที่แล้ว

      @@kcottonable egg

  • @angeloperez4758
    @angeloperez4758 9 ปีที่แล้ว +3

    __
    EL is wrong its a ray not a line that goes on forever :/ ( there's a point in E )

    • @HrsHJ
      @HrsHJ 5 ปีที่แล้ว

      I guess you imagined it the wrong way The line as whole is called L here, it is not a point. But the points D and E are on the line called L which goes on forever in both directions hence it is a line DE with an arrow we just gave it the name L.

  • @DrYing
    @DrYing 13 ปีที่แล้ว +2

    Could you please make video teaching English ? Please ! T_______T

    • @jenshover8000
      @jenshover8000 7 ปีที่แล้ว

      Nnnnooooooooo

    • @Arafat-my6fe
      @Arafat-my6fe 3 ปีที่แล้ว

      After 9 years of your comment, I am replying to your comment and hoping at this point of life, you wouldn't make the same request to Sal as you may already know English pretty well by now. 😂

  • @trintyworshipband1829
    @trintyworshipband1829 12 ปีที่แล้ว

    8:16

  • @clodgozon3968
    @clodgozon3968 5 ปีที่แล้ว

    I'm really not getting this without turning subtitles on

  • @HarpSeal03
    @HarpSeal03 10 ปีที่แล้ว

    or I (L) PI

  • @arkoams45
    @arkoams45 7 ปีที่แล้ว

    I am in 10 in Bangla version .Now how can I get help

  • @geetyroy7445
    @geetyroy7445 11 ปีที่แล้ว

    It's not that hard, I'm learning this in class.

  • @Gabe_Sert
    @Gabe_Sert 4 ปีที่แล้ว +1

    Who's here from Mr.Donovan's class?

  • @kevinlin7674
    @kevinlin7674 11 ปีที่แล้ว

    9:06..... I will call it a J...BJ XD

  • @edgarpoefan
    @edgarpoefan 12 ปีที่แล้ว +1

    ........

  • @HarpSeal03
    @HarpSeal03 10 ปีที่แล้ว

    I (L) π

  • @darkpearl88
    @darkpearl88 7 ปีที่แล้ว

    ugh, no need to over-emphasize your words it's just annoying and not at all helpful in remembering the terminology.