I am trying! It's been over 14 years that I haven't done any of it, lol. So I am only starting with the computational part first and then I will get into the more conceptual part.
@ranjitsarkar31264 жыл бұрын
@Leonhard Euler I am a real big fan of you Mr. Euler. But I cannot subscribe your channel. Because you are faking
@aashsyed12773 жыл бұрын
@@ranjitsarkar3126 who?
@aleksgornik3 жыл бұрын
Gaussian elimination sucks, it’s a bit trial and error and if you take the wrong route you go into a black whole and can’t go out of it
@jordimayorgisbert64904 жыл бұрын
I have no idea about the pretty 3rd method !!! Thank you 🙏!! I’ll give it to my students next monday !! Very nice !! (Like the D.I. Integrate method 😉)
@blackpenredpen4 жыл бұрын
Thanks for liking! Cheers!
@SahilSharma-nh8tr4 жыл бұрын
My teacher already taught me these methods 😎😎😎😎
@megauser85123 жыл бұрын
I like the 3rd method the most too!
@youkaihenge58924 жыл бұрын
When you drew that big matrix for C that face you made was hilarious knowing we all are suffering from the inverse hahaha
@blackpenredpen4 жыл бұрын
lol, imagine if it was a 4x4 matrix
@puneetmishra47264 жыл бұрын
@@blackpenredpen The third way could work for 4x4 matrix as well?
@virajagr4 жыл бұрын
@@puneetmishra4726 I guess it will work when n is odd. When n is even, the plus minus sign would mess up.
@MA-bm9jz4 жыл бұрын
Another method would be from the characteristic polynomial,by writting A^(-1) as a linear combination of A and A^2
@wduandy4 жыл бұрын
How?
@MA-bm9jz4 жыл бұрын
@@wduandy so a 3×3 matrix has a characteristic polynomial like this A^3+a_1*A^2+a_2*A+a_3*i=0 ,multiply by A^(-1) and we get A^2+a_1*A+a_2*i+a_3*A^(-1)=0 and from there you get A^(-1)
@SimonClarkstone4 жыл бұрын
@@MA-bm9jz How do you find a_1, a_2, a_3?
@MA-bm9jz4 жыл бұрын
@@SimonClarkstone you compute the characteristic polynomial,det(A-x*i),but since A is a 3×3 -a1 is the trace(since the sum of the eigenvalues is the trace),-a3 is the determinant(product of eigenvalues),all those observations come from vieta's formula,a2 is a bit more tricky,is the sum of all 2nd degree diagonal minors,or just compute det(A-x*i) and those a_i will come naturaly
@SimonClarkstone4 жыл бұрын
@@MA-bm9jz I don't know enough linear algebra to understand that unfortunately.
@dookey60994 жыл бұрын
I just finished this topic in school , finding the inverse of 3x3 is such a pain for me because I always make stupid arithmetic blunders. Just got to be careful
@SwordQuake24 жыл бұрын
The second method is best. You won't need to calculate the determinant separately if you don't have it.
@Sergeak214 жыл бұрын
WHATTT the third way is actually witchcraft. I have been wasting my time doing the second-way smh.
@wanlitan74063 жыл бұрын
24:25: "It's not a new way" Title: "Inverse of a 3 by 3 matrix (3 ways)"
@lesnyk2554 жыл бұрын
I think I like method #3 the best for manual longhand calculation, but #2 as the easiest to program..
@drpeyam4 жыл бұрын
Woohoo, I’m inverse ready 😇
@vishwanraja6663 жыл бұрын
do you play the sims ?
@egillandersson17804 жыл бұрын
The first way is the more "theorically understandable", but the third way is the coolest to perform. Once you have computed the adjugate, you can also ignore the last raw and column and use the centre to compute de determinant (if not previously done). So, an "all in one" method !
@iRam8UnderScore4 жыл бұрын
Sorry do you mean removing the first column and last row? Because that works out, whereas what you mentioned doesn't work. ??
@francine85632 жыл бұрын
thank you so much sir, you made it look easier! I just want to ask a question, regarding the 3rd way 24:30, can I use it still when solving for determinants with 4 x4 or more matrix?
@farkasmaganyos4 жыл бұрын
I really appreciated the 3rd version! Many thanks for that!
@MrKA19613 жыл бұрын
Szerintem is ez a nyerő.
@TobyBW4 жыл бұрын
Watching this while doing my linear algebra homework on inverse matrices
@tomatrix75253 жыл бұрын
Ditto
@parasgovind62714 жыл бұрын
You have the best timing!!! I literally learned this topic a few days back and always complained about how long it takes! Your third method is awesome! Thank you!
@DarthJeremy36411 ай бұрын
please note i do not think the last method applies to matrices greater than 3 x 3
@SHASHANKRUSTAGII4 жыл бұрын
Unfortunately, I knew this before u could upload this, but it is always love to see you. PS: You and Quang Tran look alike And I love you both. One for Maths One for Mukbangs
@jeffayako4 жыл бұрын
i love the last one u make it look really easy i will try writting a CPP code to compute the inverse using that algorithm
@nex4 жыл бұрын
Here's the ‘how to determinant‘ video: kzbin.info/www/bejne/ipyxlneupLecobs (Maybe put that link in the description, 曹?)
@AlfredPros4 жыл бұрын
That last trick is so cool! I wish my lecturer taught me about it!
@vinayaktyagi10014 жыл бұрын
He : inverse of a matri- Me : *adj(A) / |A|* Adjugate ? I learned it as adjoint . Well both are same anyways so doesn't really matter
@geosalatast57154 жыл бұрын
There's a guy with a goat beard who holds a pokeball, has the Picasso painting The Scream and is talking about matrices... Pure Excellence! Greets from Greece!
@ytsimontng4 жыл бұрын
And runs Marathons 🇬🇷
@daphenomenalz57844 жыл бұрын
Great video...actually Today i was trying to find some more ways to calculate the inverse of a matrix and you helped me a lot. thank you...but now I'm wondering how to compute inverse of a (n by n) matrix where, n is any unknown positive integer Please share how to do this
@blackpenredpen4 жыл бұрын
Thank you for you comment. I think, unfortunately, once we get a bigger matrix, we have to use either method 1 or method 2..
@aravinds38464 жыл бұрын
Another way to find inverse is by using Cayley-Hamilton Theorem, which gives |A -λ I | = 0 , where I is a unit matrix. When we evaluate this determinant we get an equation of degree n , where n is the order of A. The equation is in terms of λ, so replace it with A. Voila! we get an equation with variables being the matrix and constant is the unit matrix. Multiply by A inverse and get simplify the rest o the terms to evaluate A inverse
@shunmugasathishk93653 жыл бұрын
The 1st method that you've done is Gauss-Jordan method
@trueriver19504 жыл бұрын
Fourth way: apply the BPRB technique but the second matrix is not the unit matrix but this: Det 0 0 0 Det 0 0 0 Det This gives you the transpose matrix in the second example. Remember to divide the integer matrix you get by the determinant of the original. You can either divide each element, or just write a scalar multiple of (1/Det A) in front, depending what you are about to use the matrix for. This offers an insight about why there is no inverse when Det = 0 because you'd be dividing by zero... I prefer this fourth way
@helo38274 жыл бұрын
I bet no one will respond to this
@loliflower_arts488Ай бұрын
Bet lost. Where the money at? 😀
@BCS-IshtiyakAhmadKhan3 жыл бұрын
The method used in the thumbnail was already taught by my teacher last year
@rezamiau4 жыл бұрын
Great! but in the second method, you could use Cofactor Matrix to evaluate Determinant easily! so I think the second method is much more faster than the first one.
@talentedtobi6 ай бұрын
The last method is Gold. Thanks so much.
@virajagr4 жыл бұрын
Can you do proof for second method? Thank you
@GreAse0MonKey273 ай бұрын
the last method is the life saver!!! :))
@jordimayorgisbert64904 жыл бұрын
I’ve a little "improve", making the T operation over the A matrix at the first, and then work with it. You'll avoid the final arrangement for making the T. I'm based on the property Adj(A^T) = (Adj(A))^T. That's only a suggest !! ;-)
@laurensiusfabianussteven65184 жыл бұрын
The sad part is i see this when i already completed my linear algebra course :'
@angelxd70194 жыл бұрын
Gracias por compartir sus conocimientos maestro redpen 💪🙌
@6754bettkitty4 жыл бұрын
You should cover pseudo-inverses!
@tomatrix75253 жыл бұрын
Peyam - Funniest math teacher. Bprp - Coolest math teacher.
@omshandilya88884 жыл бұрын
2020 raise to the power 2019 - 2020 divided by 2020 square + 2021=N then find the sum of digits of n bro plz solve this?? trying from last 5 weeks
@megauser85123 жыл бұрын
Is that the same as N = 2021 + [ (2020^2019) - 2020 ] / 2020^2?
@XgamersXdimensions4 жыл бұрын
I took Linear Algebra over the summer (and passed!) but I’ve never seen the 3rd way! Very useful and would have saved me a lot of time
@pauljackson34914 жыл бұрын
For the 3rd method, the crossed out -4 is only used for the det. now? And can you actually start anywhere but 1,1 (where the -4 is) is easiest?
@TechnoCoderz369 Жыл бұрын
Thank you Very much!
@sabriath4 жыл бұрын
I feel like a form of cryptographic key could be constructed with matrixes somehow.....maybe this will inspire me for the next week.
@hrishikeshdube4 жыл бұрын
Hey man.! It's 2.30 In INDIA now
@rashipplaha12034 жыл бұрын
I was watching the live calc test yesterday till 4:30 am and i had a class on 8😂😂
@krish13494 жыл бұрын
So what?
@virajagr4 жыл бұрын
Can the 3rd method be extended for higher order matrices as well? That is, copy first 3 columns and rows for 4×4 instead of 2 which is for 3×3. And then take determinant for each 3×3 matrices formed inside
@ShinichiKudou20084 жыл бұрын
I think that will work for sizes of an odd number (but not even number) because when a column in a square matrix of size of an odd number is shifted to the opposite end the determinant doesn't change sign.
@virajagr4 жыл бұрын
@@ShinichiKudou2008 ah that makes sense, thanks
@vinayaktyagi10014 жыл бұрын
2 x 5 is 9 Sorry , had to do it 😂
@holyshit922 Жыл бұрын
a_{n}=1 a_{m}=-1/(n-m)(sum(a[j+m]tr(A^{j}),j=1..n-m)) This will give you characteristic polynomial and from Cayley Hamilton we will get the inverse This is not as fast as elimination but faster than cofactor method
@jackkalver464415 күн бұрын
Fun fact: Inverses can be found vertically using column operations.
@brendamartinez69553 жыл бұрын
❤
@abhisheksharmavats83264 жыл бұрын
3rd is nice
@AttilioPitt4 жыл бұрын
This is AMUUUSING! thank you! i love this trick
@pedrokalume24734 жыл бұрын
One more reason to start watching bprp is that he is now making Linear Algebra videos
@KN-tt7xu3 жыл бұрын
That 3rd method is actually very useful, thank you for showing that
@chawkichalladia18124 жыл бұрын
i remember being good at matrix in college. i remember doing that second method. this was more than 5 years ago. the only chapter that gave me hope of being good at math xD
@bsb04 жыл бұрын
I wish I watched this video yesterday. before my linear algebra final😂
@dr.rahulgupta75733 жыл бұрын
Sir I found 3'rd method the best .Congratulations for it .DrRahul Rohtak Haryana India
@saurabhin4 жыл бұрын
I know all of the method. But, i like your way of teaching ♥️
@yuliiavideo4 жыл бұрын
The third way is excellent. May I teach my students this method?
@trueriver19504 жыл бұрын
This technique applies to any sized matrix with an inverse. It is the matrix algebra equivalent of doing simultaneous equations as usually taught to students before they meet matrices.
@AttilioPitt3 жыл бұрын
The last method is very beautiful for optimazing the inverse. I really want to use it in an exam, but i think that i need to demostrate it. Could you please help me, please? Thx
@mathieus-c67613 жыл бұрын
"dididididida" (delete this, delete that) Love ur vids, keep going on !!
@archerdev Жыл бұрын
matrices bless you man, thanks for this dead cool video. Much appreciated
@21croz4 жыл бұрын
I have an Algebra exam next week, really appreciate these videos you are uploading. Greetings from Chile!
@muskyoxes4 жыл бұрын
Is it a coincidence that one of the rows of the inverse don't have the nasty 13 denominator, or is something deeper going on? It's suspicious to me that, in the cofactor matrix, the multiples of 13 happen to line up.
@DarthJeremy36411 ай бұрын
What if you have a 4 x 4 or 5 x 5 or anything like and n x n where n is greater than 3. Do we still add the two columns and rows to expand the matrix for the shortcut method ?
@lolegarcesfuster90903 жыл бұрын
can somebody clarify the rigorous name of the 3rd method in order to pre-quote the method before solving the exercise.
@ItsMeTheUser10 ай бұрын
3nd way is very clever, thanks Steve!
@tamarpeer2614 жыл бұрын
It's the same matrix as the o e for the determinant trick. Is it special?
@DilipWoad4 жыл бұрын
All the method i was knowing 😅 but i love...i taught u might have other shortcut .....the 3rd is my favourite i use it every time its easy
@chunfaimok7674 жыл бұрын
I am actually looping 9:40,13:42,15:40 those charming laughter
@otheraccount52524 жыл бұрын
Now that you have used a blue pen, are you going to rename your channel to blackpenredpenbluepen?
@alexnoussi9 ай бұрын
The 2nd way is familiar, and the third one is rather peculiarly interesting.
@nvapisces70119 ай бұрын
In my linear algebra I, we call it the adjoint matrix instead of the adjugate matrix
@JRO5124 жыл бұрын
PLEASE DO LINEAR ALGEBRA PROOFS! I need some enlightening or else I’ll fail my class
@drpeyam4 жыл бұрын
I have lots of playlists of linear algebra proofs in case you’re interested
@KAMRANKHAN-xf7iq Жыл бұрын
The Ist and 2nd methods are too hard! The 3rd one is easy and super tricky! Where the hell you learnt the 3rd method???
@VJ-dv4ub4 жыл бұрын
pure brain juice Thank you very much sir bye the way awesome beard sir
@arnaldosantoro68124 жыл бұрын
11:00 "either you like it or you hate it" Clearly hates it
@therealgoat33677 ай бұрын
"6 - 2 is... Why is that so hard?"...FELT!!!!
@mmh26952 жыл бұрын
This video is so good, now I'm ready for tomorrow's exam, thx a lot
@coleabrahams93313 жыл бұрын
I always used to use the second matrix. Thx for this
@michaelempeigne35193 жыл бұрын
Does this work for all matrices for n x n matrices with n > 3 ?
@mnqobimsizi4328Ай бұрын
me using the calculator
@legendarytaj20543 жыл бұрын
Way 3 is better if you have the determinant if not then gotta go with way 1.
@welllll...ok...2 ай бұрын
Love the humour! You thought that was it... no!
@victorrodriguez8663 жыл бұрын
does the third method work for matrices with range > 3?
@alihamad52462 жыл бұрын
Cayley-Hamilton Theorem go brrrrr!
@Olavotemrazaodenovo4 жыл бұрын
Congratulations from Brazil.
@sambhav27274 жыл бұрын
I have a doubt on characteristic equation of a matrix..For a 3x3 matrix A , we know that sum of eigenvalues = trace of A(sum of diagonal elements of A), and product of eigenvalues= determinant of A..For a 3x3 matrix,is there any significance of sum of product of eigenvalues taken 2 at a time? (i.e. (coeff of A) )
@aryanraina36314 жыл бұрын
Why are you holding a pokeball?
@Mr_flewis4 жыл бұрын
Plz answer this question Q- integral of 2x^2.dx divided by (x-1) (x-2) (x-3)
@davidgendron69554 жыл бұрын
Try partial fractions.
@Mr_flewis4 жыл бұрын
@@davidgendron6955 yes I applied that formula but
@Mr_flewis4 жыл бұрын
Here 3 algebraic functions are present how can i solve?