Easiest Proof of Pythagoras' Theorem

Proof of Pythagoras' Theorem using just basic areas and algebra in less than a minute!
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Пікірлер: 50

  • @tonitalas1757
    @tonitalas1757 Жыл бұрын

    Very clear proof of pythagorian theorem! Thank you 😊

  • @Ihavebodiesinmybasement
    @Ihavebodiesinmybasement4 ай бұрын

    INSANE!!! very well explained 🎉

  • @Bedoroski
    @Bedoroski5 ай бұрын

    Thank you. This is the most intuitive proof, no need to move the shapes around.

  • @Phymacss
    @Phymacss Жыл бұрын

    Your videos are really interesting and nice! Also, thank you for the kangaroo challenge practice course !

  • @Mathsaurus

    @Mathsaurus

    Жыл бұрын

    Thank you! Pleased to hear that it has been helpful!

  • @Bookops
    @Bookops25 күн бұрын

    Thank you now im more confused 😀

  • @Abdullah123-lx9ji
    @Abdullah123-lx9jiАй бұрын

    Very clear simple proof,very useful thank you😊!

  • @mrvalidvs2722
    @mrvalidvs2722 Жыл бұрын

    Excellent

  • @Mathsaurus

    @Mathsaurus

    Жыл бұрын

    Thanks!

  • @The_Green_Man_OAP
    @The_Green_Man_OAP6 ай бұрын

    Try this: a²+b²=(a+b)²-2ab Consider: c²+2ab Factoring: c²(1+2(a/c)(b/c))=c²(1+2sinAcosA) The value 2ab/c² is the double angle trig ratio sin2A, (see ‡ at the bottom) Consider: (a+b)²/c² This is equivalent: (sinA+cosA)² Expanding out: sin²A+cos²A+2sinAcosA Subs for 2sinAcosA & due to “†” & “‡” (bottom), this is: 1+sin2A. From “1”, have: c²+2ab=c²(1+sin2A) From “2”, have: (a+b)²/c²=1+sin2A. Therefore: c²=(c²+2ab)/(1+sin2A)=(c²+2ab)/(a+b)²/c² Multiplying by (a+b)²/c² on both sides: (a+b)²=c²+2ab => (a+b)²-2ab=a²+b²=c² …QED 😊. (†)From the compound angle formulas(‡) for sin & cos, you get double angle formulas for those, and from cos2A you get: 1-2sin²A=2cos²A-1=cos2A => 2=2(cos²A+sin²A) Therefore: 1=(cos²A+sin²A) (‡)Proof in this video: “Angle sum identities for sine and cosine” by blackpenredpen

  • @mrbagginz5963
    @mrbagginz59636 ай бұрын

    Thank you! Explained it very well too

  • @Mathsaurus

    @Mathsaurus

    5 ай бұрын

    You're welcome!

  • @jirifrantal2236
    @jirifrantal2236 Жыл бұрын

    How do you know that the shape inside the outer square is a square (with right angles)? You need to prove it. ;-)

  • @tyleravanmeter

    @tyleravanmeter

    Жыл бұрын

    I feel like it is a fairly trivial proof of simple geometry that makes it a square.

  • @jirifrantal2236

    @jirifrantal2236

    Жыл бұрын

    @@tyleravanmeter Yes, it's simple but it's necessary. 🙂

  • @bienvenidos9360

    @bienvenidos9360

    Жыл бұрын

    The triangles are congruent right triangles, so their 2 smaller angles add up to 90°. When you place them inside the square as shown, you get angle A + angle B + angle X = 180° since a straight line = 180°. Then angle A + angle B = 90°, angle X must be 90° to fulfill the side which is a straight line. This is a basic concept.

  • @shriramwarrior8936

    @shriramwarrior8936

    11 ай бұрын

    Side lenghts are identical, and inner angles are all identical. What else other than sqaure?

  • @merkezeteget
    @merkezeteget2 ай бұрын

    👏🏾☺️📐

  • @abryg8655
    @abryg8655Ай бұрын

    One of the elegants 🎩

  • @shriramwarrior8936
    @shriramwarrior893611 ай бұрын

    Clearest proof. ❤

  • @Mathsaurus

    @Mathsaurus

    11 ай бұрын

    thanks!

  • @shantamajukar291
    @shantamajukar29111 ай бұрын

    Really enjoyed bro Love from India 🇮🇳 to you❤🎉

  • @Mathsaurus

    @Mathsaurus

    11 ай бұрын

    thank you!

  • @Mehraj052
    @Mehraj052 Жыл бұрын

    Great

  • @user-kz8gw5wd9y
    @user-kz8gw5wd9y4 ай бұрын

    Where does the 2ab come from when finding the area of the larger square?

  • @aharshibasu4250
    @aharshibasu4250Ай бұрын

    Area is side^2 not (a+b)²

  • @rafiqueahamad2900
    @rafiqueahamad29009 ай бұрын

    Thanks man just have an exam and saw you really helpfull

  • @Mathsaurus

    @Mathsaurus

    9 ай бұрын

    Glad it helped!

  • @abhipatel4595
    @abhipatel45956 ай бұрын

    Very well explained

  • @Mathsaurus

    @Mathsaurus

    5 ай бұрын

    Glad it was helpful!

  • @mythologicaleditor
    @mythologicaleditor5 ай бұрын

    But how will you prove that the insife rhombus is a square with side c?

  • @KanhaWes
    @KanhaWes29 күн бұрын

    now do the detailed explanation

  • @mrinmoy2689
    @mrinmoy26899 ай бұрын

    SUPERB

  • @lalaromero8907
    @lalaromero89079 ай бұрын

    Im freaked out!! 👍

  • @uwu69420uwu
    @uwu69420uwu3 ай бұрын

    0:01

  • @samyogdhakal3431
    @samyogdhakal34314 ай бұрын

    I've a doubt. Why we make bigger square a square having length a+b not a rectangle with Side 2a and 2b and still area of smaller square will be c^2

  • @rimasen4725

    @rimasen4725

    Ай бұрын

    It won't be a square of side c but a rhombus of side c . So area wont be c2 but 2ab . Now 2ab+2ab = 2a×2b =4ab . Its not going anywhere 🙂

  • @icyy9864
    @icyy98644 ай бұрын

    Beautiful

  • @Mathsaurus

    @Mathsaurus

    4 ай бұрын

    Thank you

  • @cazanid802
    @cazanid8029 ай бұрын

    Can i ask why theres only (a+b)2 why not 4?,and also where u can find that 1/2ab,

  • @Mathsaurus

    @Mathsaurus

    9 ай бұрын

    the 1/2 ab is for the triangles and there are 4 of them. But there is only one square so only one (a+b)^2

  • @stu1002
    @stu10027 ай бұрын

    The problem with the proof is that it's not obvious why the sides of the large square are all a+b

  • @Mathsaurus

    @Mathsaurus

    5 ай бұрын

    If you prefer you could take the four congruent triangles as the starting point put together to make the large square - then I think it’s clear the lengths are the same and the shape inside is a square follows from the angles in the triangle

  • @kingofgamers7718
    @kingofgamers77185 ай бұрын

    Bhaskaras proof

  • @user-kz8gw5wd9y
    @user-kz8gw5wd9y4 ай бұрын

    Where does the 2ab come from when finding the area of the larger square?

  • @hana-yr1tr

    @hana-yr1tr

    4 ай бұрын

    same, im confused on this part too. if u figure it out, lmk!

  • @juan9154

    @juan9154

    3 ай бұрын

    The whole square is essentially just (a+b)^2 cuz u have to multiply length by width to get the area. If u expand (a+b)^2 u get (a+b)(a+b) which you can then get (a^2)+2ab+(b^2) by using foil