Believe in geometry, not squaring both sides!

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We will solve the equation that has two square roots sqrt(16-x^2)+sqrt(9-x^2)=5 with a cool geometric triangle trick. In the end, we will also see if ChatGPT can solve this equation by using geometry. Check out a similar video on the proof of the Pythagorean Theorem and its inverse: • Pythagorean Theorem & ...
0:00 Solving sqrt(16-x^2)+sqrt(9-x^2)=5 by using geometry
5:15 Check out Brilliant
6:13 Can ChatGPT solve this with geometry?
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Пікірлер: 450

  • @blackpenredpen
    @blackpenredpen5 ай бұрын

    Get started with a 30-day free trial on Brilliant: 👉brilliant.org/blackpenredpen/ ( 20% off with this link!)

  • @ISoldBinLadensViagraOnEbay

    @ISoldBinLadensViagraOnEbay

    5 ай бұрын

    I’M JOSEPH STALIN’S MIGHTY FROG

  • @deltalima6703

    @deltalima6703

    5 ай бұрын

    Your "phd friend" video was hilarious, I was laughing about that for hours. The one with the "just identify it" line, the handwaving, and the topology of the circle. :D

  • @player3572

    @player3572

    5 ай бұрын

    Hey bprp! Can you do this math equation? It was in my test. sin(cos(tan(x)))=1

  • @leonardobarrera2816

    @leonardobarrera2816

    5 ай бұрын

    But base on the video, you could use the pythagorams inverse formula, also you have on you channel!!! It would be more intresting!!

  • @M0n3Y1g

    @M0n3Y1g

    5 ай бұрын

    try explaining this (ANIMATION VS MATH) video explains about mathematics and I still don't understand, can you explain it please?

  • @chaosredefined3834
    @chaosredefined38345 ай бұрын

    I think this is a spot for sybermath's substitution trick. Let a = sqrt(16 - x^2). Let b = sqrt(9 - x^2). Then, we are given that a + b = 5. Also, from the definitions of a and b, we have a^2 = 16 - x^2, and b^2 = 9 - x^2. Subtracting those, we get a^2 - b^2 = 7. So, (a + b)(a - b) = 7. But, since a + b = 5, we get 5(a - b) = 7, or a - b = 1.4. Add that to a + b = 5, and we get 2a = 6.4, or a = 3.2. Plugging that back in to a = sqrt(16 - x^2). 3.2 = sqrt(16 - x^2), so 10.24 = 16 - x^2. x^2 = 16 - 10.24 = 5.76 = 2.4^2. So, x = +/- 2.4. I will agree, using the "standard" approach of squaring both sides and untangling the mess that that produces is... a giant pain. But, sybermath's substitution trick avoids that nicely.

  • @yoav613

    @yoav613

    5 ай бұрын

    Nice,i like sybermath trick too,but no need for any tricks here.just square sqrt(16-x^2)-5 and -sqrt(9-x^2) and you get after simple algebra x^2=5.76 so x=+-2.4

  • @abdelrahmanayman8415

    @abdelrahmanayman8415

    5 ай бұрын

    I squared both sides (25=16+9-2x^2+2√((9-x^2)(16-x^2))) after that u get x^2=√((16-x^2)(9-x^2)) Then squaring both sides u will end up 25x^2=16×9 Solving this simple equation u get postive or negative 12/5

  • @chaosredefined3834

    @chaosredefined3834

    3 ай бұрын

    @@abdelrahmanayman8415 If you are going to square both sides... Subtract one of them first. sqrt(16 - x^2) = 5 - sqrt(9 - x^2) Then square 16 - x^2 = 25 - 10 sqrt(9 - x^2) + 9 - x^2 Rearrange 10 sqrt(9 - x^2) = 18 Divide by 10 sqrt(9 - x^2) = 1.8 Square 9 - x^2 = 3.24 Rearrange x^2 = 5.76 Then solve for x x = 2.4 or -2.4 Notice that you don't have to deal with as big an equation as you did.

  • @samueldeandrade8535

    @samueldeandrade8535

    3 ай бұрын

    sybermath's trick? What makes this trick to be "sybermath's trick"?

  • @Avighna

    @Avighna

    3 ай бұрын

    That is so fucking cool, thank you so much for sharing this!?!??

  • @S.sanvi4
    @S.sanvi45 ай бұрын

    That ChatGPT attempt 💀💀

  • @anto8722

    @anto8722

    5 ай бұрын

    “Ai will take over the world!” Meanwhile, AIs: “tHrEe pLuS fOuR eQuAlS fIvE”

  • @Macieks300

    @Macieks300

    5 ай бұрын

    It was ChatGPT3.5, not ChatGPT4, so of course it's not going to be good at math.

  • @saj_f0

    @saj_f0

    5 ай бұрын

    @@Macieks300 you say chat GPT 4 is good at math then

  • @zaidtalib4513

    @zaidtalib4513

    5 ай бұрын

    @@Macieks300 gpt 4 is equally garbage at math lmao

  • @Macieks300

    @Macieks300

    5 ай бұрын

    @@saj_f0 Yeah, it's way better at math.

  • @jarikosonen4079
    @jarikosonen40795 ай бұрын

    Probably a lot of important questions (like up to 3rd deg polynomials) are geometry related.

  • @puleraleaooa8110

    @puleraleaooa8110

    5 ай бұрын

    This is a very interesting question 🙋

  • @d.h.y

    @d.h.y

    5 ай бұрын

    Euclidean geometry is the future 😆

  • @dominicellis1867

    @dominicellis1867

    3 ай бұрын

    You can always construct a geometric figure that represents an algebraic relationship. That is what makes analysis so beautiful.

  • @dominicellis1867

    @dominicellis1867

    3 ай бұрын

    @@studiouskid1528 if it’s fake, you can just use the half real half fake plane. The noobs call it complex but I’ve always thought it was simple.

  • @dominicellis1867

    @dominicellis1867

    3 ай бұрын

    @@studiouskid1528 2 real axes and one imaginary axis. x->z = a+bi.

  • @cloudgamer1244
    @cloudgamer12442 ай бұрын

    He used a blue pen

  • @hr07m

    @hr07m

    10 күн бұрын

    Fuck

  • @basantakumarshaw6440
    @basantakumarshaw64405 ай бұрын

    Now I will use geometry whenever I can to solve funky algebraic equations.

  • @rekikhayder
    @rekikhayder5 ай бұрын

    Great simple geometric solution 😊

  • @3rpi3r44
    @3rpi3r445 ай бұрын

    Really cool problem! Thank you as always

  • @patum3588
    @patum35885 ай бұрын

    Also there exist inverse pythagoran where 1/a^2 + 1/b^2 = 1/d^2 so in our case it would be : 1/4^2 + 1/3^2 = 1/x^2 and it would be equal to this anwswer

  • @glogenuniversal6047
    @glogenuniversal60473 ай бұрын

    This was fun! thank you for your videos

  • @sifilo
    @sifilo5 ай бұрын

    I'm loving this series of yours, the "Believe in __ not ____". Could we get a trigonometry edition?

  • @blackpenredpen

    @blackpenredpen

    5 ай бұрын

    Great idea! I will have to think about it.

  • @user-jo5lh5oj6o
    @user-jo5lh5oj6o5 ай бұрын

    Glad to see you again! Nice solution!

  • @OmPrakash-pc1ec

    @OmPrakash-pc1ec

    3 ай бұрын

    ти ща де

  • @ricardoguzman5014
    @ricardoguzman50145 ай бұрын

    Nice way to solve. I solved a variation of this problem earlier this year based on a video posted by Peyam. There's an amazing detail contained in the problem. x² = 4² - [√(16-x²)]². x² = 3² - [√(9-x²)]². So 4² - [√(16-x²)]² =3² - [√(9-x²)]². Add [√(16-x²)]² and [√(9-x²)]² to both sides of the equation and you get 4² + [√(9-x²)]² = 3² + [√(16-x²)]². And so you obtain a variation of a pythagorean quadruple, a² + b² = c² + d². By using different values for the side lengths and perpendicular of the triangle, you can generate an infinite number of rational or whole number solutions to the problem of finding a² + b² = c² + d².

  • @AnthonySouls
    @AnthonySouls5 ай бұрын

    I used Google Bard, and this was the best answer I got so far (for anyone interested): Prompt: Use geometry and geometric relationships to calculate sqrt(16-x^2)+sqrt(9-x^2)=5 While the given equation can be solved algebraically, using geometry and geometric relationships adds a visual and intuitive approach. Here's how we can solve it: 1. Define the geometric elements: Imagine a right triangle ABC, where AC = 5 (from the right side of the equation). AB and BC are the two roots we need to find, represented by sqrt(16-x^2) and sqrt(9-x^2) respectively. Point D lies on AC such that AD = sqrt(16-x^2) and DC = sqrt(9-x^2). 2. Apply the Pythagorean theorem: For both right triangles ABD and BDC, apply the Pythagorean theorem: AB^2 = AD^2 + BD^2 = (16-x^2) + BD^2 BC^2 = BD^2 + DC^2 = BD^2 + (9-x^2) 3. Combine the equations: Add the two equations resulting from the Pythagorean theorem: AB^2 + BC^2 = 2BD^2 + 16 - x^2 + 9 - x^2 Substitute AC^2 for AB^2 + BC^2: AC^2 = 2BD^2 + (16 + 9) - 2x^2 Substitute 5 for AC: 25 = 2BD^2 + 25 - 2x^2 4. Solve for BD^2: Simplify the equation: 2BD^2 = 2x^2 BD^2 = x^2 5. Relate BD to AB and BC: Recall that BD represents the common leg of the two triangles: AB = sqrt(BD^2 + AD^2) = sqrt(x^2 + (16-x^2)) = sqrt(16) = 4 BC = sqrt(BD^2 + DC^2) = sqrt(x^2 + (9-x^2)) = sqrt(9) = 3 6. Verify the roots: Check if the calculated values of AB and BC satisfy the original equation: sqrt(16-x^2)+sqrt(9-x^2) = 4 + 3 = 7 However, since squaring both sides of the original equation introduces extraneous solutions, we need to consider negative values as well. 7. Negative roots: Repeat steps 3 to 6 with negative values for AB and BC: -AB = -4, -BC = -3 sqrt(16-x^2)-sqrt(9-x^2) = -4 - 3 = -7 This also satisfies the original equation. Therefore, the solutions for x are: x = ±sqrt(16) = ±4 (positive roots) x = ±sqrt(9) = ±3 (negative roots) Conclusion: Using geometric relationships and the Pythagorean theorem, we found that the equation sqrt(16-x^2)+sqrt(9-x^2)=5 has four solutions: x = ±4 and x = ±3. This approach provides a visual understanding of the problem and the relationship between the squares and square roots involved.

  • @AnthonySouls

    @AnthonySouls

    5 ай бұрын

    Here is the CHATGPT version for the same prompt: To solve the equation sqrt(16-x^2) + sqrt(9-x^2) = 5, we can use geometric relationships and algebraic manipulation. Let a = sqrt(16 - x^2) and b = sqrt(9 - x^2). The given equation becomes: a + b = 5 Now, let's square both sides of the equation to eliminate the square roots: (a + b)^2 = 5^2 Expand the left side: a^2 + 2ab + b^2 = 25 Replace a and b with their original expressions: (sqrt(16 - x^2))^2 + 2sqrt((16 - x^2)(9 - x^2)) + (sqrt(9 - x^2))^2 = 25 Simplify the expression: 16 - x^2 + 2sqrt((16 - x^2)(9 - x^2)) + 9 - x^2 = 25 Combine like terms: 25 - 2x^2 + 2sqrt((16 - x^2)(9 - x^2)) = 25 Subtract 25 from both sides: 2sqrt((16 - x^2)(9 - x^2)) = 0 Divide both sides by 2: sqrt((16 - x^2)(9 - x^2)) = 0 Now, since the square root of a product is zero only when the product is zero, we can set each factor inside the square root equal to zero: 16 - x^2 = 0 Solve for x: x^2 = 16 x = ±4 and 9 - x^2 = 0 x^2 = 9 x = ±3 So, the solutions to the equation are x = -4, -3, 3, 4. However, we need to check if these values satisfy the original equation because sometimes extraneous solutions may arise during the manipulation. For x = -4: sqrt(16 - (-4)^2) + sqrt(9 - (-4)^2) = sqrt(0) + sqrt(7) = 0 + sqrt(7) ≠ 5 For x = -3: sqrt(16 - (-3)^2) + sqrt(9 - (-3)^2) = sqrt(7) + sqrt(0) = sqrt(7) ≠ 5 For x = 3: sqrt(16 - 3^2) + sqrt(9 - 3^2) = sqrt(7) + sqrt(0) = sqrt(7) ≠ 5 For x = 4: sqrt(16 - 4^2) + sqrt(9 - 4^2) = sqrt(0) + sqrt(7) = 0 + sqrt(7) ≠ 5 None of the solutions satisfy the original equation. Therefore, there are no real solutions to the given equation.

  • @bmn6292

    @bmn6292

    3 ай бұрын

    @@AnthonySouls The error in this calculation is that when you removed 25 from both sides, you also removed -2x^2 from the left side without adding 2x^2 to the right side.

  • @SteveMathematician-th3co
    @SteveMathematician-th3co5 ай бұрын

    This is gold! Thank you for such a useful video!

  • @ethanhall6965
    @ethanhall69655 ай бұрын

    I really love math. But similar to basketball where I’ll never be an NBA player, I’ll never be a great mathematician. The insights needed are just beyond my ability. However, I’ll never give up because I really enjoy learning.

  • @RandomCatFromFrance

    @RandomCatFromFrance

    3 ай бұрын

    Same for me, tho i still dream of finding something new, even if small.

  • @Formula7Driver

    @Formula7Driver

    2 ай бұрын

    Just keep learning and you'll surprise yourself how good you can become

  • @mrinaldbhat9921

    @mrinaldbhat9921

    2 ай бұрын

    hey! dont demotivate yourself that way. enough practice and determination can make anyone good at anything.

  • @ethanhall6965

    @ethanhall6965

    2 ай бұрын

    @@mrinaldbhat9921 Thanks. I'm still working at it. I won't give up.

  • @gopalsamykannan2964
    @gopalsamykannan29645 ай бұрын

    Very good teaching. Thank you !

  • @General12th
    @General12th5 ай бұрын

    I always love having a look inside!

  • @ludmilaivanova1603
    @ludmilaivanova16033 ай бұрын

    very interesting approach!

  • @StereoSpace
    @StereoSpace2 ай бұрын

    I would never have thought of approaching the problem that way. Very interesting!

  • @zhelyo_physics
    @zhelyo_physics5 ай бұрын

    Super interesting video!

  • @dankestlynx7587
    @dankestlynx75872 ай бұрын

    i used angles to find the value of x in the end , assume one angle tetha rest are either 90-tetha or tetha which makes it much easier

  • @panyachunnanonda6274
    @panyachunnanonda62742 ай бұрын

    Wow, Thank you, so amazing, I love this technique.

  • @sergeygaevoy6422
    @sergeygaevoy64225 ай бұрын

    It is sort of isomorphic transform I think. Like Laplace or Fourier transfom. Many things are isomorphic even when they are very different.

  • @table5584

    @table5584

    5 ай бұрын

    Isomorphisms!

  • @pauselab5569

    @pauselab5569

    5 ай бұрын

    don't think that it is an isomorphism at least not in the usual sense.

  • @sergeygaevoy6422

    @sergeygaevoy6422

    5 ай бұрын

    @@pauselab5569 You can map some structure to another structure (sqrt() to a triangle). Map some operation to another operation (addition to position in space). Then you should unmap the result. The only problem here that we cannot get the negative result in geometry. We cannot be sure there no other colutions using this mapping. That is true. But we do have ideal mappings: quaternions ~ 2x2 matrices, all quaternion with the same vector direction ~ complex numbers (a plane in 4D) multiplication of complex numbers & quaternions ~ rotations (quaternions have parallel and orthogonal parts rotate differently) The more interesting question lies in Physics: DO gravity and electromagnetism share the same nature OR are they only isomorphic!? If two thing follow the same axioms they will follow the same theorems.

  • @samueldeandrade8535

    @samueldeandrade8535

    3 ай бұрын

    What ... are you talking about?

  • @alextaunton3099

    @alextaunton3099

    3 ай бұрын

    ​@@samueldeandrade8535isomorphisms. Get with the program

  • @jadewolf3416
    @jadewolf34165 ай бұрын

    This will be a very good watch!

  • @eknathraykar3572
    @eknathraykar35723 ай бұрын

    Nice approach.

  • @thatapollo7773
    @thatapollo77735 ай бұрын

    After making the triangle, instead of equations areas you can use the "inverse" Pythagoras theorem ie 1/x^2 = 1/3^2+1/4^2

  • @TheQuadraticFormula319
    @TheQuadraticFormula3195 ай бұрын

    I have always loved the geometrical representation of equations (mostly from 3blue 1brown) but this method is just ♥

  • @2001herne

    @2001herne

    3 ай бұрын

    You learn to love geometric representations in engineering - on the engineering HSC (Australia(NSW) Higher School Certificate) exam it's valid to solve force diagram problems either analytically, or by drawing the diagram to scale and measuring. If you're neat enough, it's a lot quicker, and about as accurate.

  • @user-xh7mq8ty8m
    @user-xh7mq8ty8m5 ай бұрын

    This is not for to the video, but just for those who see this including blackpenredpen. I found a potential formula for the summation of 1/x^n where n is greater than or equal to 1. d^n / d r^n { ln[ (x+r-1)! / (r-1)! ] }/n! with r being a constant equaling 1. ( Note I used d for the partial derivative of r).

  • @user-xh7mq8ty8m

    @user-xh7mq8ty8m

    5 ай бұрын

    It is actually d/dr {ln[ d^(n-1) / dr^(n-1) (x+r-1)!/(r-1)!]} and the bounds of summation are 1 and infinity.

  • @mike1024.
    @mike1024.3 ай бұрын

    That was a neat approach to this problem! When I read the title, I thought more about circles than right triangles.

  • @AyberkDurgut
    @AyberkDurgut5 ай бұрын

    Great solution!

  • @ronaldokado834
    @ronaldokado8342 ай бұрын

    Congratulation! It is fantastic!!!

  • @EyeSooGuy
    @EyeSooGuy4 ай бұрын

    Hey there, Steve. Since I’m in Info Tech, I also had to learn CS (computer science). The whole new other “dimensions” of math like binary (0 and 1), octal (0 to 7) … I’m skipping the decimal part bc that’s the math we’re at right now …. Hexadecimal (base-16 that’s 0 to 9 and A to F representing 10 to 15. Like 1F for example …. That’s 31 in decimal and so forth. You get the gist), base-32, base-64 and finally, base-85. I learned there’s a multiplication table of hexadecimals. Google it up all you want. Now! I’m curious. Can you do algebra, trig, geometry and/or even calculus WITH only hexadecimals? I’d LOVE to see a vid of you attempting on applying the Euler and the pi to hex format. Hehe. Pretty please?! Can you do that?! You can even consult with a comp sci expert on this, if CS is not your expertise. Wink.

  • @fletch7311
    @fletch73115 ай бұрын

    would you be able to do a video explaining how to solve equations such as 2^x + 3^x = 2 or 2^x + 5^x = 1 and other similar cases?

  • @caiolira09
    @caiolira095 ай бұрын

    so fun! thank you!

  • @EmpyreanLightASMR
    @EmpyreanLightASMR5 ай бұрын

    On a recent StarTalk podcast episode, Prof. Charles Liu said on his (presumably at-home) exams, he asks his students to use chaptgpt to solve a problem, and then to explain why it's wrong 😂

  • @travisretriever7473
    @travisretriever74733 ай бұрын

    *Standing Ovation!* Always lovely to see elegance in math problems like this. :)

  • @tamirkarniely6913
    @tamirkarniely69135 ай бұрын

    I thought about an interesting question and I couldn't solve it. I suggest it as a video idea: Consider the function f(x) = Sigma from n=1 to x of (1/n) Where x is a Natural number. Now plot points on a regular x-y plain, where the x-values are the x value of f(x), and y-values are the Smallest Common Denominator of all fractions created by f(x) at that x. In short, a coordinate is: (x, SCD). For clarrification, the first few points are: (1,1), (2,2), (3,6), (4,12), (5,60), (6,60), (7,420), (8,420), (9,3690), (10,3690)... The goal is to find the function g(x) that outputs the SCD according to f(x) for every input x, where x is Natural. Bonus: if possible, expand the definition of g(x) so that the input is in the Real domain.

  • @arghyadeepdasgupta908
    @arghyadeepdasgupta9082 ай бұрын

    Great method sir ❤️😯

  • @clashwithsun5449
    @clashwithsun54494 ай бұрын

    Question) If Y={x such that x is a positive factor of the number [(2^p-1)(2^p - 1)] , where (2^p - 1) is a prime number}. Write Y in the rooster form

  • @Karl-Ruprecht-Kroenen1
    @Karl-Ruprecht-Kroenen14 ай бұрын

    That was a cool problem Thank you 😊

  • @kingbeauregard
    @kingbeauregard2 ай бұрын

    I did this one the brute force way, and it was surprisingly not too bad. It was a miracle of canceling terms so that it solved pretty neatly.

  • @spacetimeslasher
    @spacetimeslasher5 ай бұрын

    Imperial! As an math aspirant i will use it

  • @d.h.y
    @d.h.y5 ай бұрын

    What a beautiful solution 🤩🤩

  • @user-ld5cw4ez1m
    @user-ld5cw4ez1m4 ай бұрын

    I'm your silent fan, I really love the way you help us in math, especially me but, I am curious. How did you become master at math? how much time do you solve math before? can you make a video for it?

  • @hdsjshheishhs1907
    @hdsjshheishhs19075 ай бұрын

    Try this: 1+power(2+power(3+…+power(n+…,1/n),1/3),1/2)=?where n is natural and goes to infinity.

  • @fabientuizat1129
    @fabientuizat11292 ай бұрын

    tres élégant !! merci !!

  • @giovannicorno1247
    @giovannicorno1247Ай бұрын

    Brilliant, I did not think to use build the second triangle in that way. I made a mental calculation and found sqr 7 is a good solution😊.

  • @tubax926
    @tubax9265 ай бұрын

    Im gonna use this question to show my friends that geometry is beautiful and not just shapes

  • @manyifung5411
    @manyifung54115 ай бұрын

    If it is not right angled triangle we can use 1/2 ab sin(x) to find the area

  • @Avighna
    @Avighna3 ай бұрын

    You never miss my guy

  • @mawavoy
    @mawavoy5 ай бұрын

    Great video 👏

  • @plantho2497
    @plantho24975 ай бұрын

    I have a question, if you have n points of n possible colours, the equation for number of combinations should be(correct me if i'm wrong) n^n. If you then have n points possibly connected by any combination of lines you should have nC2 lines between the points, but since each line can be in 2 different states(there, and not there) the formula for combinations should be (nC2)^2. Can you please find and explain the non integer value of n where the 2 equations are equal?

  • @agnichatian
    @agnichatian3 ай бұрын

    Even without the perfect numbers leading to the second right triangle, Heron's formula can be used to get the second relation for the area: let semiperimeter s = (a+b+c)/2 then area A = sqrt[ s(s-a)(s-b)(s-c) ]. In this problem s is 6 and A is also 6.

  • @janoaleksandriano4425
    @janoaleksandriano4425Ай бұрын

    Beautiful!

  • @zeroplays9915
    @zeroplays99154 ай бұрын

    Can you make a video about this interesting problem--> If z = x + iy is a complex number where x and y are integers. Then, the area of the rectangle whose vertices are the roots of the equation----> w z^3 + z w^3 = 350, where w=conjugate of z

  • @mikezilberbrand1663
    @mikezilberbrand16633 ай бұрын

    Well done, Alan!

  • @meshiraj
    @meshiraj5 ай бұрын

    The Solution was pretty impressive . When I glanced at the video's thumbnail, my instinct told me the answer might be something like the square root of 5, and it turned out to be true since the square root of 5 is roughly 2.4. Here's how I approached it: I focused on the second part of the equation, Sqrt(9-x^2), and thought that for any x to make the equation true, this part must be a perfect square. Since it's 9 minus something, and the nearest square (less than 9) is 4, I realized that the subtracted value of x must be 5 to make it work. Voila! When I cross-checked this value with the first part, Sqrt(16-x^2), and calculated with calculator it fits to say that LHS = RHS! :)

  • @devtated8213
    @devtated82133 ай бұрын

    Just noticed that even x = 0 as well as x= +- 12/5 Since, we are using the 3-4-5 triplet to find the results The one of the trivial solutions to the problem!! Awesome explanation!!!! Looking forward to more such videos

  • @GrimAxel

    @GrimAxel

    3 ай бұрын

    Except x=0 doesn't work. When x=0, sqrt(16-x^2)=4 and sqrt(9-x^2)=3. But 4+3=7, and 7≠5.

  • @mokouf3
    @mokouf35 ай бұрын

    1: If the resulting triangle isn't a right triangle, we can use Heron's formula. 2: Haha, ChatGPT did it wrong again! ChatGPT is not good at math, but quite good at programming!

  • @nathanjiang100
    @nathanjiang1005 ай бұрын

    I was hoping you’d use the inverse pythagorean theorem 1/a^2 + 1/b^2 = 1/h^2 then you get 1/x^2 = 25/144 so x = +/- 12/5

  • @jakehobrath7721
    @jakehobrath77214 ай бұрын

    @blackpenredpen Can you please do a break down of the integral arctan(x)/x^3 dx? I’m fascinated by it.

  • @juliomora9151
    @juliomora91512 ай бұрын

    La longitud de la altura referida a la hipotenusa en un triángulo rectángulo es igual al producto de los catetos dividido por la hipotenusa, x=(3*4)/5

  • @BobChess
    @BobChessАй бұрын

    "Trust in Geometry" people when meet "i"

  • @Sirius37641
    @Sirius376413 ай бұрын

    Q: can you solve x^4+x^2+1=0 by using the quadratic formula? . . . Ans: yes (x^2)^2+x^2+1=0, and now we have a quadratic equation in terms of x^2 x^2=-1+-sqrt of 1^2-4(1)(1)/2(1) x^2=-1+-isqrt of 3/2, and now take the square root of both sides, we get: x=+-sqrt of( -1+-isqrt of 3/2), and now we can square both the numenator and the denominator, we get: x=+-i+-isqrt of 3/2 (x is equal to plus or minus i plus or minus the square root of 3 all over 2)

  • @hinley2615
    @hinley26155 ай бұрын

    Great video, you earned my subscribed. I love watching these questions where there is close to none knowledge prerequisites but still gets you thinking.

  • @alexandermorozov2248
    @alexandermorozov2248Ай бұрын

    Любопытно! Хорошо бы ещё провести проверку 😘

  • @anthonyr.748
    @anthonyr.7485 ай бұрын

    with similar triangles you can see the answers with ratios (either sub triangle works), 5 : 3 as 4 : x implies x=12/5

  • @christianchan1144
    @christianchan11445 ай бұрын

    can this be generalized for solutions of the form: sqrt(a^2 - x^2) + sqrt(b^2 - x^2) = c where a,b,c are a recognized pyth. triple?

  • @martys9972
    @martys99723 ай бұрын

    Very nice solution! While it is true that the solution would not be as nice if the RHS were not equal to 5, the geometrical method works for those cases as well, since the area of the triangle can be obtained by Heron's formula. For RHS = 6, the answer is +/-sqr(455)/12.

  • @mausmalone
    @mausmalone2 ай бұрын

    I got the answer but instead of using the area of the triangle I used simple ratios. Because I know two angles of the right side triangle, I know that it ALSO is a 3-4-5 triangle, so its sides would have the same ratios as any other 3-4-5 triangle. That gave 3/x=4/5. Very very easy to calculate.

  • @k.turtle6145
    @k.turtle61453 ай бұрын

    You can also say the triangles are similar and create a ratio of the side lengths to the hypotenuse. 4/5 = x/3

  • @Vanessa.W
    @Vanessa.W3 ай бұрын

    Can you try the integral of x/sinh(x) from -∞ to ∞? It comes out to a really nice answer, but I have no idea how you’d actually solve it…

  • @ppmax9392
    @ppmax93924 ай бұрын

    May i ask since n[sin(180degree/n)] helps u calculate pi. If lim n--> infinity, is n(sin(180degree/n)) = pi?

  • @ppmax9392

    @ppmax9392

    4 ай бұрын

    anyone answer me pls ty

  • @kylebeschler03
    @kylebeschler035 ай бұрын

    what was up with holding that red white and black stuffed looking thing in the past? I was curious when i saw your past vids. Interesting content btw! Very creative, different, and analytical.

  • @AnimalSyndicate
    @AnimalSyndicate3 ай бұрын

    I f**ing love this guy!

  • @user-on7ct8em3m
    @user-on7ct8em3m5 ай бұрын

    Please, I want you to create a formula to solve the equation ax^3+bx^2+cx+b And this one too ax^3+bx=n

  • @looooonooooooooooooooooooooong

    @looooonooooooooooooooooooooong

    3 ай бұрын

    Look up cardano formula

  • @user-st8hy2ms4x
    @user-st8hy2ms4x4 ай бұрын

    老师可以讲一下怎么积分Tan(cos(x)) 从0 到2pie吗

  • @mahdikissoum2913
    @mahdikissoum29135 ай бұрын

    Hi Blackpenredpen, I have two things to tell you! First of all, could you make the 100 integrals file (the first video) freely available? Secondly, I offer you a huge integral! The integral of 1/(1+x^5). Otherwise good luck! Bye !

  • @dhruv2004
    @dhruv20042 ай бұрын

    that was awesome

  • @Nikioko
    @Nikioko3 ай бұрын

    Euclid's Height Theorem: h² = pq Euclid's Leg Theorem: a² = cp, b² = cq

  • @user-kf1gt1tb8r
    @user-kf1gt1tb8r3 ай бұрын

    Very fine I belived in geometry.Thank you

  • @mayanksharma2595
    @mayanksharma25953 ай бұрын

    Good question

  • @phat_khiep
    @phat_khiep5 ай бұрын

    There are n multiple choice questions, each question has i options to choose from. Step 1: Randomly choose the mth option (with m less than or equal to i and m greater than or equal to 1) in the first multiple choice question Step 2: Repeat the option in the 1st multiple-choice question in the next (k-1) multiple-choice questions. Step 3: To choose the option in the (k+1) multiple choice question, we will choose in the following way for each case: Case 1: If the option chosen in the kth multiple choice question is the mth option (with m smaller than i), then choose the (m+1)th option. Case 2: If the option chosen in the kth multiple choice question is the ith option, then choose the 1st option. Step 4: Repeat Step 2 and Step 3 for multiple-choice questions from the (k+2)th multiple-choice question to the nth multiple-choice question. Each multiple choice question has only 1 correct answer. Let t be the number of multiple-choice questions answered correctly in n multiple-choice questions, t follows the Bernouli distribution. Find k to t max.

  • @Ladka13-rx7eq
    @Ladka13-rx7eq3 ай бұрын

    Respected sir, Find the value of the following questions geometrically in the principle value range: (a) arcsin(sin 23) (b) arcsin(sin24) Where both 23 and 24 are in radian.

  • @LichKingg23
    @LichKingg235 ай бұрын

    That was beautiful.

  • @TGIies
    @TGIies4 ай бұрын

    i used heron's formula for the other area and equated it with the common area formula. even though yours is easy.

  • @KushagraThakur.
    @KushagraThakur.3 ай бұрын

    Thanks

  • @user-xp2ri8uh8w
    @user-xp2ri8uh8w2 ай бұрын

    That was brilliant

  • @kidamaroo
    @kidamaroo22 күн бұрын

    This is brilliant

  • @luizrobertocamargo5864
    @luizrobertocamargo58644 ай бұрын

    I need help with a question. Please. Knowing that lim(x-->-2)f(x)/(x^2)=1, which is the value of lim(x-->1)f(x^2-3x)/[(x+8)^(1/2)]? Answer bellow. Answer: 5/3

  • @Sriansu-to4ds
    @Sriansu-to4ds3 ай бұрын

    I used rationalisation and it also works here. On rationalising (16-x²)½+(9-x²)½=5, We get (16-x²)½-(9-x²)½=7/5. Adding both equations we can eliminate one term and square the resulting equation to get x.

  • @someonespadre
    @someonespadreАй бұрын

    For this to work the larger triangle has to be a right triangle. No, I was wrong here. Consider a 13-14-15 triangle. Used Heron’s formula to get area=84 and height above 15 side is 11.2. Sqrt(169-x^2)+sqrt(196-x^2)=15, x=+/-11.2. This is great.

  • @yourgarage4175
    @yourgarage4175Ай бұрын

    we can also able to do this in another way: ✓16-x²=(5-✓9-x²) then we can square both sides it will be very easy

  • @greedskith
    @greedskith2 ай бұрын

    did same when i saw thumb, saw you did the same, i thought i got a smart solution haha

  • @user-ni4pk1mc6j
    @user-ni4pk1mc6j3 ай бұрын

    Damn...I was always an algebra guy but now I think geometry also kicks. Thanks sir.

  • @juancarlossanchezveana1812
    @juancarlossanchezveana18123 ай бұрын

    Excellent

  • @savaesmek
    @savaesmek5 ай бұрын

    this is so elegant damn

  • @dongorongo1735
    @dongorongo17355 ай бұрын

    If it was not a right triangle, you could use Heron's formula for the area

  • @mrmezclicks1908
    @mrmezclicks19085 ай бұрын

    Is there any chance you could have a look at how to solve x^(x+1) = 2