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@lapicethelilsusboy4912 жыл бұрын
I'll ask again: Are you okay?
@leonardobarrera28162 жыл бұрын
Thanks for the video
@jamespat79752 жыл бұрын
How to solve this integral question ? Integral [ ( 1/x^2 * (1+x^4)^0.5) ] dx ?
@Abdul-ot3lu2 жыл бұрын
Is brilliant worh
@hustler3of4culture32 жыл бұрын
Brilliant
@louisvictor34732 жыл бұрын
Log triangles are naturally very hard to manipulate, on account of their large size and weight.
@fasebingterfe63542 жыл бұрын
I agree
@U014B2 жыл бұрын
I never wood've thought about that.
@theabyss56472 жыл бұрын
I think it's not because they're heavy but because of their temperature. We're taking about an ln triangle and liquid nitrogen is not mechanically problematic.
@davidbrisbane72062 жыл бұрын
Log triangles are good for the environment. They trap a lot of CO2 in them.
@chitlitlah2 жыл бұрын
"naturally" But natural logs are a bit easier to work with than other logs.
@bartekabuz8552 жыл бұрын
Fun fact: If you try the same thing with sine you will get x=pi/6 and with cosine x=pi/4
@joaomatos65982 жыл бұрын
How?
@JirivandenAssem2 жыл бұрын
Probs u use trig. Identities
@AlchemistOfNirnroot2 жыл бұрын
For a sin(x), sin(2x) and sin(3x) triangle and then you got the cos(x) solution as a result of the trig identity?
@astha_yadav2 жыл бұрын
If u differentiate at the right triangle square law thing, removing the powers, then raise from e as powers removing ln , then solve the quad eqn u get 3/2 which is a correct soln Edit: actually there is some thing wrong with this method though i haven't figured out what I accidentally checked for lnx + ln2x = ln3x rather than the square form, so the soln is wrong Not deleting incase someone wishes to help out
@JirivandenAssem2 жыл бұрын
@@astha_yadav who asked🤣he asks about the trig version
@mathmathician82502 жыл бұрын
You should change the side length to ln(3x), ln(4x) and ln(5x) to make people to remind of the famous 3-4-5 right angled triangle. :)
@artsmith1347 Жыл бұрын
WolframAlpha gives two solutions for log^2(3 x) + log^2(4 x) = log^2(5 x) x≈0.25848 x≈0.67166
@thexoxob9448 Жыл бұрын
The 0.25 solution doesn't work because 3 times that is less than 1.. which means length is negative, which is impossible
@MasterofNoobs69 Жыл бұрын
@@thexoxob9448it is possible with complex numbers, and you are then squaring it to make it real. The i-1-0 triangle is an example of absurd triangles you can create like this. The math works out, even if the geometry doesn’t.
@zzciobzz296311 ай бұрын
@@thexoxob9448less than 1 isn't negative. it's between 0 and 1
@Gust522 жыл бұрын
The "Fading In" Intro is so much better!
@blackpenredpen2 жыл бұрын
Thanks!!!
@CaradhrasAiguo492 жыл бұрын
5:12 the nice little detail about completing the square here is if you do NOT simplify ln(2) - ln(3) to ln(2/3), but add [ln(2) - ln(3)]^2 to [ln(3)]^2 - [ln(2)]^2 on the RHS, the [ln(2)]^2 will CANCEL 10:00 an approximation is x = 3.8549
@Jack_Callcott_AU2 жыл бұрын
@CaradhrasAiguo49 I agree, that is the number I got! 👍
@Rex-xj4dj2 жыл бұрын
I did that but still got about 2.45
@general_paul Жыл бұрын
I agree with your result
@pietrofubini78332 жыл бұрын
I finally managed to get to the solution of the problem all by my self I feel so proud, it is all thanks to your videos
@davidbrisbane72062 жыл бұрын
I only feel relieved when I solve maths problems.
@joebrinson50402 жыл бұрын
BPRP, you are my favorite math teacher. Thanks for another video.
@blackpenredpen2 жыл бұрын
Thank u!
@petek13652 жыл бұрын
I started working this out myself until I reached the quadratic in LnX at which point I realized there was a much easier way to find the solution. All I had to do was watch the video and bprp would work it out for me :)
@dimitrisg632 жыл бұрын
great video! I have been watching you since 2018 and your content is constantly getting better! good job mr. bprp.
@dimitrispapadakis21222 жыл бұрын
Είμαστε συνονόματοι και έχουμε την ίδια εικόνα προφίλ :)
@junaidhasrat112 жыл бұрын
@@dimitrispapadakis2122 don't tell me this is your alt account
@blackpenredpen2 жыл бұрын
Thank you!
@dimitrisg632 жыл бұрын
@@junaidhasrat11 no hahaha
@1A26WANCHEUKNAM1A2溫綽楠4 ай бұрын
0:03 I heard love triangle ...
@josephtraverso27002 жыл бұрын
The sudden chimpmunk voice jump scared me at 8:45
@kent6314202 жыл бұрын
Dear bprp, I have a question, and I'd appreciate it if you solve it in your next video: Find the max/min value for sinA*sinB*sinC where A, B, and C are three angles in a triangle (A+B+C=pi) Thank you
@simonwillover41752 жыл бұрын
Picks complex A, B, C
@bebizambi3922 жыл бұрын
Possible solution?: since A, B and C are angles which form a triangle, you could take C=π-(A+B). Then, sinC= sin(A+B) due to allied angles. Resulting expression is sinA*sinB*sin(A+B). I used maxima and minima for above expression using partial derivatives and got the answer.
@davidp44272 жыл бұрын
Help me out here. A + B + C = 180° so 180° = pi ??? Am I missing something?
@nguyenphungdunganh3941 Жыл бұрын
@@davidp4427 radians since we're adults now
@Razhy042 жыл бұрын
This x is actually a solution to log(x)^2 + log(2x)^2 = log(3x)^2 for any log base greater than one. Bases between one and zero satisfy the equasion but they don't make a right triangle as log(x) would be negative. The other solution of the quadratic formula will give the right answer for bases between one and zero.
@jens55732 жыл бұрын
I used to hate math, but this guy has somehow an interesting way of explaining things, so I somehow just got hooked lol 😂
@GammaFZ2 жыл бұрын
same, he’s the reason I’m obsessed with math too
@AfaqueAhmed_2 жыл бұрын
0:00 Just a man coming out of the blue with a Blue pen and Red pen and a sweet Log problem for us .
@emperorhirodripo586311 ай бұрын
This video was soo satisfying, because I always realised what he was about to do, split seconds before he actually did it
@Goldslate732 жыл бұрын
Please please please please please do another marathon session. Really need it. Calculus. Maybe Laplace, Fourier, Bessel etc. Please?
@e.s.r58092 жыл бұрын
It's simply fascinating how the quadratic formula pops up like this. More than once a non-scientist/engineer/mathematician has said to me, "They made us memorise the quadratic formula in school. Why? Where will that ever be relevant?" And the answer is... well, everywhere! If you could pick only one formula to memorise, I think this would be a strong choice!
@Someniatko2 жыл бұрын
It's even better to understand how to derive this formula! It's pretty easy!
@cristianrdz7667 Жыл бұрын
@@Someniatko Yeah, is easy
@otiswebb57832 жыл бұрын
Thanks for this vid. I solved something similar inspired by this problem: instead the sides of the triangle were cosh x, cosh(2x) and cosh(3x). Took a lot of algebraic manipulation but the final answer was pretty cool. Maybe another video?
@otiswebb57832 жыл бұрын
There are 2 real solutions for x
@barndoor12622 жыл бұрын
Has anyone noticed the WIZARDRY at the first 3 seconds of the video?!? I haven't yet watched this but the first few seconds scared the bejezsus outta me. Why did they do that? The editor must have had a chuckle.
@DynestiGTI2 жыл бұрын
I love how you just pop into existence in the beginning
@usdescartes2 жыл бұрын
If you solve the generalized problem of using sides ln(nx), ln((n+1)x), and ln((n+2)x), you get: x = (n+2)/(n (n+1)) * e^sqrt(2 * ln((n+2)/n) * ln((n+2)/(n+1)))
@Lucretiel2 жыл бұрын
I took me a while to notice how seamlessly he was switching between red and black and now I’m extremely jealous
@tomctutor2 жыл бұрын
Almost the same as BPRP direct analysis, notice that: log(2x) - log(x) = log(2) log(2x) + log(x) = log(2x^2) from which the product gives the difference of squares, [log(2x)]^2 - [log(x)]^2 = log(2)log(2x^2) = log(2)[log(2)+2log(x)] ...eq(1) from the triangle pythagoras, [log(2x)]^2 + [log(x)]^2 = [log(3x)]^2 = [log(x) + log(3)]^2 ...eq(2) eq(2) - eq(1) gives, 2[log(x)]^2 = [log(x) + log(3)]^2 - log(2)[log(2)+2log(x)] a quadratic in log(x), let u = log(x), u^2 - 2[log(3/2)]u - log(6)log(3/2) = 0 solve for u using quadratic formula and your done x = e^(1/2){ 2log(3/2)+- sqrt[4[log(3/2)]^2 +4log(6)log(3/2)] } etc..
@82rah Жыл бұрын
At 9:09 you discard the negative sqrt. But this leads to a positive value of x: (3/2) exp( -sqrt( ln(3/2) ln(9) ) ) = .536676; (3/2) exp(+-sqrt( ln(3/2) ln(9) ) ) = 3.854877
@shadowgamer6383 Жыл бұрын
Even though it's a positive value of x, the side length of the triangle which is ln x will become negative. And we can't have triangle with negative sides
@shreyaschaturvedi8851 Жыл бұрын
@@shadowgamer6383exactly
@manavrana225 Жыл бұрын
Note: x needs to be greater than 1.5 as sum of two sides need to be greater than third side or the difference between 2 sides needs to be less than the third side.
@eckhardtdom2 жыл бұрын
0:00 Bro came from imaginary world to real world
@Khusbuhasrat6 ай бұрын
😂😂😂
@crustyoldfart2 жыл бұрын
Neat problem - more subtle than I at first thought - which was that you would be proving an identity. The solution can be summarized as follows : put a(x) = ln( x ) ; b(x) = ln( 2*x ) ; c(x) = ln( 3*x ) ; if a(x)^2 + b(x)^2 = c(x)^2 -> x = { 3*N/2, 3/(2*N) } where N = e^y ; y = sqrt(-2*ln(2)*ln(3)+2*ln(3)^2) -> N = 2.569917715.. x = { 0.5836762755, 3.854876572 } The open question is : when are mathematicians going to admit that not only are calculators here to stay but also math software ?
@racool9112 жыл бұрын
This was a really good log rule refresher lol
@itzmrinyy74845 ай бұрын
This is actually one I was able to solve by myself! Very cool, I had to attempt a variety of different methods before thinking to expand ln²2x into (ln2 + lnx)², but once I did that everything was clear.
@reubenmanzo2054 Жыл бұрын
After a very exhaustive effort, I got the following solution: x=e^{-ln(2/3) (+/-) sqrt[2ln(3/2)ln3]}
@papasalt8823 Жыл бұрын
I believe I messed up somewhere along my working and don't feel like restarting. But from a number theory perspective, couldn't this be solved through Euclid's formula? Often used only with integers, but it applies to the real numbers too. If a^2 + b^2 = c^2. Where: a = m^2-n^2 = lnx b = 2mn = ln2x c = m^2+n^2 = ln3x We can raise everything to the power of e. Then rearrange for x in each equation. And set 3x to be equal to the sum of each equation. (3x = e^a + e^b + e^c). I'm not sure where to go from here though, but I haven't worked through far enough to think about that section, and I'm too lazy to do it since I already mucked up once.
@voidkfox9526 Жыл бұрын
You forgot to distribute the square power in the b^2 of the cuadratic formula. (2ln(2/3)^2 is 4(ln(2/3))^2, not 4ln(2/3) as you say in the video
@computernerd11012 жыл бұрын
The approximate value of x is 3.85488
@Smosh7i9 ай бұрын
What about x = 0.583676
@computernerd11019 ай бұрын
@@Smosh7i That does work algebraically, but if x < 1, then ln(x) < 0. Geometrically, it doesn't make sense for the edge of a triangle to have a negative length.
@DokterrDanger2 жыл бұрын
7:50 Best part: SHWOO!
@rishavbagri42112 жыл бұрын
If u are bored solve this find range of a for all value of y lie in R as y = (ax²+3x-4)/(3x-4x²+9) . . . . Ans- a€(1,7)
@nikhilsoni24032 жыл бұрын
Wow!! I solved it by a different method (but your method is much simpler and shorter) and got this answer x = 3^[a(a+ sqrroot2)] Where a = sqrroot {[log₃(3/2)]} I thought my answer is wrong ,but after using the calculator, I found that my answer is correct !! 🥳🥳
@chazzbunn78112 жыл бұрын
I got the same answer, I wanted to check it before watching this video. Checking it with algebra by putting the solution back into the original equation proved difficult, much harder than the actual problem in fact.
@tambuwalmathsclass2 жыл бұрын
Amazing creativity
@SuperYoonHo2 жыл бұрын
Thanks
@BrijeshsChannel2 жыл бұрын
I've started watching your vids since a month and the way u explain is so cool. i could understand understand calculus at the age of 14 thanks to you! #yay
@blackpenredpen2 жыл бұрын
Glad to hear 😃
@steventrimble22752 жыл бұрын
ln(3x)^2 = ln(2x)^2 + ln(x)^2 Then take the derivative of both sides above and cancel common factors ln(3x) = ln(x) + ln(2x) ln(3x) = ln(2x^2) ln(3x/2x^2) = 0 ln(3/(2x)) = 0 then raise to the power of e 3/(2x) = 1 x = 3/2
@AndreyNsk892 жыл бұрын
Applying derivatives to both sides of the equation does not produce an equivalent equation. For example equation x = x + 1 doesnt have solutions, but if you take derivatives it will become 1 = 1, i.e. it is correct for all x.
@e.s.r58092 жыл бұрын
The other issue here (besides the one Andrey pointed out-- I think you meant square root, not derivative) is that you still have to take (ln3 + lnx)^2 = ln3ln3 + 2ln3lnx + lnxlnx. (p + q)^2 =/= p^2 + q^2 sqrt(p^2 + q^2) =/= p + q (p + q)^2 = p^2 + 2pq + q^2 By Pythagoras (substituting lnx = z, ln3 = a, ln2 = b for the sake of everyone's sanity) we expand our brackets and reach: z^2 + 2az + a^2 = 2z^2 + 2bz + b^2 Gathering, simplifying, and substituting back a and b: z^2 + ln(4/9)z + ln(6)ln(2/3) = 0 As you can see, it's a quadratic with two solutions and no common factors to cancel. If you took the exponential of both sides now you'd reach an impasse (or at least something very gross). Remember you have to take exp of the entire expression, and by log rules, those multiplying lns would end up as powers: alog(b) = log(b^a) lnxlnx = ln( x^(lnx) ) 1 = exp{ ln[ x^(ln(x)) × x^ln(4/9) × ... Grim! 😅
@procerpat92232 жыл бұрын
this is a beautiful problem, your presentation is so impeccable I have watched it several times🙋🏻♂️
@SG-lh7up2 жыл бұрын
I saw your great older video on x^x. Would you consider making a video on plotting x^x (in 3 dimensions) for Real input and complex output? I tried to sketch the full 3d curve, with the x axis being Real and running perpendicular to the complex plane which is used for the output of x^x. So the x axis is the Real input; the y axis is the Real output and the z axis is the imaginary output. So the y and z axes form the complex plane output of the Real x input. So you have a simple exponential-looking 2d curve for positive x, it crosses the real y axis (or has a limit at x=0) at y=1, but the curve then becomes a complex shrinking spiralling "vase" shape for negative x. It's the "smoothness" of the curve as it crosses the y axis and changes from Real 2d to Complex 3d that I can't visualize. Would you consider making a video on this 3d graph and discuss the 3d smoothness of the real-complex transition at x=0 ? i.e. what's the limit of the 3d angle of the complex curve at x=0. AND: on this graph is x^x at x=0, a forbidden indeterminate point or is it equal to 1 ?
@saujanyapoudel8910 Жыл бұрын
In my take, I factored out the 4 from the square root resulting in the product of the square root and 2 then I factored out 2 in the numerator and cancelled it with the 2 in the denominator. When you didn't do the same I expected you would have some twist so I was afraid if I have to rewrite it again.
@tahabouthouri7803 Жыл бұрын
Ln9 can be 2ln3 so u simplify 2 and 1/2 and you'll get (ln3)² and you simplify the square root and ull get e^(ln3) and you simplify more and you'll finally get 9/2
@ItsPungpond98 Жыл бұрын
Bprp's top 10 catchphrases 1. Let's do some math for fun! 2. Oh my god! Looks pretty crazy! 3. Wouldn't it be nice... 4. Don't forget the plus C! 5. Today, we have the integral of... 6. Let's go to the complex world! 7. I don't like to be at the bottom, I like to be on the top. 8. Bring this down down! 9. Don't worry, don't worry. 10. The best friend of the black pen is the red pen.
@desiaasm2 жыл бұрын
X is approximately 3,8549 and is a transcendental number!
@shivamchouhan50772 жыл бұрын
Actually it is 3.854765
@desiaasm2 жыл бұрын
@@shivamchouhan5077 Yeah I just rounded it mate
@shivamchouhan50772 жыл бұрын
@@desiaasm But you added comma (,) instead of dot(.) So your answer was 38549
@nuclear30112 жыл бұрын
@@shivamchouhan5077 in some countries (like Poland, where I live, for example) people use commas to mark the decimal point and use dots in big numbers e.g. 1.000.000
@shivamchouhan50772 жыл бұрын
@@nuclear3011 Oh thanks for telling I didn't know that one, btw this can lead to calculations errors in some cases.
@antonyqueen65122 жыл бұрын
Just a tip for quadratic equations: use simplified form of the solutions when coefficient of the linear term is even as it was the case here, i.e,: ax + 2bx + c =0 => x= [-b +|- sqrt(b^2 - ac)]/a 😉 With a=1, even simpler x= - b +|- sqrt(b^2 - c)
@anastasissfyrides29192 жыл бұрын
Much more preferable to divide by the common factor than memorizing yet another formula
@kangalio2 жыл бұрын
i know it as x²+px+q => -p/2±sqrt((p/2)²-q)
@antonyqueen65122 жыл бұрын
@@anastasissfyrides2919 it’s not memorising new formula, it’s simplifying the 2’s
@NoNameAtAll22 жыл бұрын
- b/2 you forgot to divide b by 2
@antonyqueen65122 жыл бұрын
@@NoNameAtAll2 no I didn’t. That’s the whole point. It is simplified. You don’t have the division by 2. The coefficient of at x is even: 2b, thus -2b/2a= -b/a and sqrt[(2b)^2 - 4ac]/2a= sqrt[b^2 - ac]/a With the coefficient a of x^2 being a=1 you have the simplified solution as indicated in the comment above ☝️
@2012tulio2 жыл бұрын
After the second step just replace lnx by u and then continue that would be easier
@mr.shgamingguy2 жыл бұрын
Hypotenuse and legs are on the both side of the triangle.
@BlastinRope2 жыл бұрын
Tbh in calc 2 it wasnt the calc that got me but the occaisonal algebra trick
@kalmes2 жыл бұрын
That was actually a pretty fun problem.
@Peter_19862 жыл бұрын
blackpenredpen always comes up with interesting problems.
@samocali2 жыл бұрын
I love these videos
@yqisq69662 жыл бұрын
Guys this solution works! My love triangle problem is gone, thanks to this.
@runnow265510 ай бұрын
you can simplify a litle further because ln(a)ln(b) = ln(a^b) so ln(3/2)ln(9) = ln((3/2)^9) and then you can find x=3/2 * e^sqrt(ln(19683/512)), looking at that now I can actually see why you didn't but I don't wanna waste the time I spent making this comment
@DrLiangMath2 жыл бұрын
Wow, wonderful topic and excellent presentation!
@sssilky33172 жыл бұрын
I knew I was wrong when the answer I got was super long, roughly 3 times longer than the one you got. I checked both of their exact values to make sure it wasn't just a different way of expressing the same value and it wasn't :(
@milmi__95822 жыл бұрын
Thank you
@aliexpress.official2 жыл бұрын
Challenge: find x such that: log(ax)^2 + log(bx)^2=log(cx)^2 for arbitrary a,b,c
@europeankid982 жыл бұрын
x = panda
@domc37432 жыл бұрын
Let x= e^u for an easier time... Great video though :D
@halid94572 жыл бұрын
x ≈ 3.85488
@Fred-yq3fs2 жыл бұрын
This is not too hard. Just apply the Ln formula, solve a quadratic equation, and take the exp. A year 11 should be able to do it. Takes less than a page. Great exercise and great content.
@davidbailis8415 Жыл бұрын
0:00 It’s true, bprp has super speed.
@davidbrisbane72062 жыл бұрын
I thought he said, "Love triangle" 😂🤣🤣
@latestmoviesforall2 жыл бұрын
you should simplify the exponential of the square root.
@Bts.121_42 жыл бұрын
You are brilliant👍 ☺ I love your dedication
@reidflemingworldstoughestm13942 жыл бұрын
Pretty cool algebra 2 problem.
@lotis6441 Жыл бұрын
cant I use the power rule for logs at 2(ln2)(lnx) so that 2lnx^(ln2) => lnx^(2ln2) => lnx^(ln4)?
@manavrana225 Жыл бұрын
That 2 goes to power of not power of lnx so it wiil be (ln(x²))^(ln2)
@joemcz2564 Жыл бұрын
Excellent video, but I will say that I feel like one of the solutions is missing. While I understand why you made the decision to make ln(x) strictly positive, I feel like it's more in the spirit of math to consider the negative solution as well. When I did it I interpreted a negative length to be a normal length but scaled in the opposite direction, and thus drew the triangle upside down. When you draw it out, it's a totally valid right triangle.
@asmmusic63362 жыл бұрын
Can you explain some math famous problems like the zeta function or something like that
@alikanan70112 жыл бұрын
I like this idea
@shreyaschaturvedi8851 Жыл бұрын
For everyone,, the answer is x = 3.8548
@mcgyverlouw88812 жыл бұрын
Great stuff here. When I saw the thumbnail my first thought was IS THIS POSSIBLE? Any other type of functions we can use for the sides of the right angled triangle? What about e^x?
@oenrn2 жыл бұрын
He did e^x in another video.
@NightSkyJeff2 жыл бұрын
I like crazy pythagorean triple questions. I have one for you... Can you find a pythagorean triple (a, b, c) such that (1/c, 1/b, 1/a) is also a pythagorean triple?
@charlesstimler92762 жыл бұрын
The golden ratio rules!
@whocares123722 жыл бұрын
What is the answer plz
@endeavourer10732 жыл бұрын
.
@Dviih11 ай бұрын
Shouldn’t the final solution be x = (3/2)+e^(sqrt(ln(3/2)*ln9)) ?
@jamespat79752 жыл бұрын
How to solve this integral question ? Integral [ ( 1/x^2 * (1+x^4)^0.5) ] dx ?
@ciiil88022 жыл бұрын
Can you do 100 Linear Algebra video
@MrShad2 жыл бұрын
Your videos are amazing!!
@alibekturashev62512 жыл бұрын
Idea for the math for fun: calculate sin(e) This will be literally 'approximation of sine'
@chenshan49732 жыл бұрын
what a incredible video..
@duckpilot962 Жыл бұрын
whats the answer
@mathadventuress2 жыл бұрын
couldnt you just exponentiate to get rid of the ln? e^ln(x)^2+e^(ln(2x)^2=e^ln(3x)^2??
@gcewing2 жыл бұрын
Now I'm wondering whether there are any "log-Pythagorean triples", i.e. integers a, b, c such that (ln a)^2 + (ln b)^2 = (ln c)^2. If there are, how would one go about finding them?
@Utesfan1002 жыл бұрын
Bonus points if you use Lambert's W function
@HebertMusingarimi-jw4wj Жыл бұрын
Well educative
@UStrom31692 жыл бұрын
Did he forget the + between the 3/2 and e at the final answer or did I miss sth?
@D7mh762 жыл бұрын
At 7:01 isn’t wrong? Because 2/3 /6 is equals 4. It’s same as 2/3 / 1/6 so we flip second and change the operation into multiplication
@Noctarc2 жыл бұрын
0.6666.../6 = 0.1111... not 4
@D7mh762 жыл бұрын
@@Noctarc oh yes i get it now, thank you. I wrote it as 2/3.1/6 but forget that it is 2/3//6-double lines is for longe division line-.
@RchandraMS2 жыл бұрын
ln x is a straight line??!! Side of a triangle??? ... Amazing
@Deejaynerate Жыл бұрын
isn't it fine for ln(x) to be negative since you have to raise it to the e's power anyway, which is always positive? EDIT: nevermind, I checked the other solution and realized the leg of the triangle would be negative.
@jacekskurkiewicz48512 жыл бұрын
Your t-shirt made me think that the golden ratio will appear in the answer...
@bjarnivalur63302 жыл бұрын
I was really hoping for it to work for all X
@Kcite2 жыл бұрын
dang the intro is smooth
@blackpenredpen2 жыл бұрын
Thanks!
@Dalton12942 жыл бұрын
The solution is approximately 3.85488
@ridwanwase74442 жыл бұрын
Help me to find integral of x^2/x^4+3 im in distress
@tororo1122 жыл бұрын
The other solution you have excluded is also positive: x≈0.58368 x≈3.8549 Please correct
@Phoenix-nh9kt2 жыл бұрын
X is positive but the log would be negative. So we cannot have a triangle with negative side length. Thats why the only option correct is the second one
@tororo1122 жыл бұрын
Ah right. Somehow I didn't realise this. Thanks a lot for the correction!
@Uni-Coder2 жыл бұрын
What about exponential triangle problem, exp(x), exp(2x), exp(3x) ?
@davidhowe69052 жыл бұрын
I tried this just now; first of all, thought it was impossible - then noticed my basic algebra error! I got x = 0.2406 (4 decimal places). Similar method; use Pythagoras then simplify to get quadratic in exp(2x) giving exp(2x) = (1 + sqrt(5))/2 (I think this is correct)
@carrdesch95342 жыл бұрын
Me, a physicist: "Let ln(2) = -alpha, ln(3) = beta, ln(x) = y. Now just substitute the sh** out of this and voila, we have a general formula that can be fed to a computer". I hate dealing with numbers directly, it's such a hassle and the risk of error is much higher than just doing algebra.
@alienbsg2 жыл бұрын
I solved it by splitting ln(2x) into ln2+lnx and ln3x=ln3+lnx Then by pythagoras theorem we get (ln2+lnx)²+(lnx)²=(ln3+lnx)² (ln2)²+2(ln2(lnx)+2(lnx)²=(ln3)²+2(ln3)(lnx)+(lnx)² (ln2)²-lnsolved it by splitting ln(2x) into ln2+lnx and ln3x=ln3+lnx Then by pythagoras theorem we get (ln2+lnx)²+(lnx)²=(ln3+lnx)² (ln2)²+2(ln2(lnx)+2(lnx)²=(ln3)²+2(ln3)(lnx)+(lnx)² (2ln2lnx)-(2ln3lnx)+(lnx)²=(ln3)²-(ln2)² ln(x)(2ln2-2ln3)+lnx²=ln(3^ln(3)÷2^ln(2)) (lnx)²+ln(4/9)lnx-ln(3^ln3÷2^ln2)=0 Sub Y=lnx Y²+ln4/9Y-ln(3^ln3/2^ln2)=0 One solution is Y≈1.3493 Since Y=lnx X=e^Y=e^1.3493 X≈3.855 Other solution Y≈-0.5384 X≈e^-0.5384≈0.584
@captainkarma73742 жыл бұрын
Please dont tell me you typed all that 💀
@alienbsg2 жыл бұрын
@@captainkarma7374 was tedious but that's how proofs are lmao
@asparkdeity87172 жыл бұрын
X=0.58 not a solution as then ln(X) < 0 for one of the triangle sides
@NoNameAtAll22 жыл бұрын
@@asparkdeity8717 why is that a problem? if x
@asparkdeity87172 жыл бұрын
@@NoNameAtAll2 this problem represents side lengths of triangles, all of which must be positive, yet lnX < 0 so isn’t a solution; u just need one extra sentence saying this solution should be disregarded