Quick determinant trick

Here is a useful trick that will save you a lot of time when calculating determinants! It only works for 3x3 matrices though, but still pretty neat! Enjoy this beautiful linear algebra adventure
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[@AnkitSharma-ef7md]

I just love the way professor drops his marker at the end proving that he is the boss. It is a nice rule to calculate determinant. Professor, I guess it is called "Sarrus Rule". Please correct me.

[@floccinaucinihilipilificat6749]

i prefer to call it the "rule of sarrus" cause that makes it sound like a wizard spell

[@salmazubair]

Does it work on any matrix 4*4, 5*5 ?

[@kormosmate2]

A fascinating thing about this method, is than you can "use" all sides of the matrix. Meaning you can copy the last two columns to the left side of the matrix, and here's the punch line, you can even copy the respective rows to above or below the matrix, and make similar diagonals. It will yield the same result!

[@f3ynman44]

Cool, thanks!

[@visitor--]

I'm so happy this professor still replying to others comments,nice trick i was looking for a short-cut to find the determinant of 3×3,thanks sir it helps me a lot

[@jaikumar848]

Dr payam! Any shortcut to find inverse of matrix?

[@thomasthedankengine5400]

The best method I've found has been Montante's method. It is in my opinion faster than any other.

[@adityadwivedi4412]

Adjoint is the fastest acc to me

[@pinklady7184]

jaikumar848 I was hoping that too.

[@youkaihenge5892]

For any square matrix just set it up as A = [v1,...,vn | I ] and do Guassian Elimination until you arrive at A^-1 = [ I | v1,...,vn]. Where I= identity matrix of the particular n×n size that is being inversed. Check the determinant 1st or else your doing useless computations!

[@MRdg005]

See Nishant vora sir video... He has given one step trick to find inverse

[@antflam7473]

I know this vid is 2 years old but dude. Literally awesome. Saved so much time when I just needed a quick refresher on how to do the problem. I went to organic chemistry tutor; he literally did something way more complex than what we did in class (he still isn't bad though) GG im dropping a sub

[@drpeyam]

Thank you!!!

[@Jaojao_puzzlesolver]

How I finish my math test with *style* 1:11

[@alfiealfie35]

*pen drop*

[@JustAaryeah23]

THE PEN DROP WAS SO SATISFYING ......LIKE U NAILED IT

[@kachidawarrior5232]

does this trick work for the 4 x4 matrix too??

[@optimisticallydead8819]

You are a life saver🤧❤

[@vivovivi5703]

It's sarrus method isn't it?

[@Apollorion]

Yes but no: it is not the case that it isn't sarrus method because it is the Rule of Sarrus aka Sarrus's rule aka Sarrus' rule.

[@adarshabasnet2491]

@@Apollorion what? Its the same thing.

[@popkornking]

He's just memeing

[@Tharun-wk6rj]

This is the smartest golden retriever ive ever seen

[@JackKing-b4u]

The mic drop at the end lol, legend

[@AlexGreeneHypnotist]

There'll be an extra helping of sacrificial grain at the altar of Hypatia, Leibniz and Gauss tonight. Why couldn't they have taught us this at school when I were a lad?

[@PeterBarnes2]

They did kind of. The standard method is exactly the same but with no intuition for the nice symmetries of it with all the parallel diagonals and anti-diagonals, because the standard method just doesn't illustrate how the columns wrap around (demonstrated here by drawing copies of the columns). There is a problem, though, because 4x4 and larger matrices include products which aren't over straight lines, diagonal or anti-diagonal.

[@Brien831]

@@PeterBarnes2 lets be honest here, anyone past the first semester at university never calculates a determinant by hand anyways. Except for 2 by 2 matrices and other simple cases.

[@PeterBarnes2]

@@Brien831 I'm in community college still, but I'll go along with that, sure.

[@otaku8783]

I learned a new way to solve determinant

[@spaceandtimescience6080]

Make a video on polar conatruction or geometric bundles

[@Brixxter]

A shame this doesn't work for R^4 and above

[@Kdd160]

Well, isn’t it the sarrus rule??

[@prasadmarathe7332]

Thanks a lot sir the trick is so helpful ❤😊

[@drpeyam]

Most welcome 😊

[@sharpnova2]

technically this method uses more multiplication operations than the regular way. (if I'm not figuring incorrectly, it uses 12 multiplications and 5 additions and the regular way uses 6 multiplications and 5 additions.. but the sign flips across the sub determinants probably count as multiplications as well so the two methods are hard to compare) but it very beautifully illustrates the wrap-around symmetry of matrices. you could append columns on the left or rows above and below and it would work as well very nice

[@mike_the_tutor1166]

Pen drop is the new QED. Change my mind.

[@orangeinfotainment620]

thank you man!

[@umerfarooq4831]

I needed this thanks so much I'm constantly looking for videos which make functions easier "sweet 16"

[@kamlesh25kr]

Sir you are just amazing, thanks for great tricks.

[@houseflyer4014]

My friends say i draw my matrix brackets weird. Nice to know someone qualified uses the same ones as I do.

[@anaskhalid2862]

Can I use this method in exams. If the questions says "Find the determinant without expanstion (by using properties)."

[@drpeyam]

Sadly not

[@cancer101thefundamentalsof4]

Peyam's maid: "What the f%$# are all these marks on the floor all the time?"

[@tomoki-v6o]

Regle de Sarus !

[@ntandoyenkosizungu7011]

Thank You🔥🔥🔥🔥🔥🔥

[@Motishay]

Holy shit THANK YOU

[@Akihikoo_]

Thanks!

[@charleyfeng2054]

Isn't this just the permutation definition of the determinant, from which the commonly used method is derived from?

[@abishithjoy]

Dr payam sir........ You are as God to me Thank God This is a big ticket to pass the 12th exam 🙏🏻🙏🏻🙏🏻🙏🏻

[@AwaisAli21m]

Thank you very much 😘

[@himanshucj261]

How will I apply in 4×4 matrix

[@drpeyam]

It doesn’t apply, unfortunately

[@Potatoedits17]

That's fcking Sarrus rule, dammit

[@ezu8501]

my man

[@PositronQ]

Good trick

[@rohunse5555]

Nice

[@AlfonsoNeilJimenezCasallas]

Genius!

[@matteovetri]

TyrannoSarrus rex 🦖

[@NaodWedi]

Thanks bro i am tired to find it😮😮😮😮

[@manjumanl5279]

I just created a playlist called shortmathculc ,next video is how to calculate the inverse of a Matrix.

[@hsjkdsgd]

You're gonna damage the tip of marker pen doing that stunt in the end😀

[@adwans1491]

You believe -5 x -2 is -10 ?

[@drpeyam]

You forgot about the extra -1

[@psjt9230]

Great 👍👍

[@Cs_aadda]

OMG UNBILIVABALE

[@Cs_aadda]

hello sir can plaese make eigen vector shotcut trick because my exam is coming plese ASAP. I AM ALREDY CHECK IN PLAYLIST BUT NOT AVAILABLE

[@sonusaini-nm9xc]

Wow

[@adityadwivedi4412]

I thinkyou are teaching linear algebra this semester

[@drpeyam]

No, why?

[@adityadwivedi4412]

@@drpeyam just guessing

[@negativespace5035]

nice sir

[@juma21347]

How is that any better than Sarrus? You are literally doing the same operations plus you have to write the extra lines

[@SahilTrumboo]

Who knows the trick already 👇👇👇

[@pawankumar-hk5fn]

Exactly same while writing ROW NUMBER ALONG WITH

[@yashnachugh6910]

Mane bera tha

[@jfcrow1]

Trick yes. But is it computationally more efficient. No

[@pawankumar-hk5fn]

I already used this .. before

[@wduandy]

Laplace >>>> Sarrus

[@tomzwinkels6940]

This man -2×-5=10 not -10

[@tgx3529]

This is any trick. This is a rule os Sarrus

[@titirshachakravarty9522]

Pen drop

[@ravizsz]

Answer isn't coming

[@AsianSquatsandEats]

goat!

[@bsmith6276]

This is precisely the method taught to me when I was first introduced to determinants in my high school algebra class.

[@mistadude]

why doesn't this work on 4x4 matrix

[@amosbanda9637]

I love the ending 😂😂😂

[@RohanShah-k4j]

You need more subs. As a Rutgers student taking lin alg this is a life saver ty. I hope this comment can make your day. I know video is old but the thing about math is that new students are born every day.

[@drpeyam]

Thank you so much!! It really means a lot to me 😁 I almost went to rutgers to teach actually!

[@yabaliyu3418]

Yes we believe it -10

[@sfarsi6]

-5*-2 isn't 10 ?

[@畢瀏明]

There's one more -1, so finally -10

[@sfarsi6]

@@畢瀏明 I didn't see that minus

[@pinklady7184]

Inverse of matrix next, pretty please.

[@bprpfast]

Next time, drop your phone at the end of the video

[@robsbackyardastrophotograp8885]

Good stuff- I love the two column method! Looking fresh in the new channel pic :)

[@mohamedallouche5873]

did i just learn this in my last year of college ? OMG my method was way harderrrrrrr

[@abhisekpanda5165]

Rank = 58 or 19 ?

[@jamesjohn2537]

Supper easy method! Thanks a lots

[@rui_i139]

Sarruss

[@shahzebAli2001]

😂 Just loved your actions ❤

[@thinkjin]

U r legend

[@MokshagnaGoudK]

[@sreelekshmisaji1043]

I luvvv itt❤❤❤

[@benque7491]

lmao my teacher taught this on our regular class already

[@drpeyam]

Good for you?

[@pinklady7184]

Great method! 😍😍😍 I have just created a *bookmark* with your problem & solution and slipped that inside a thick calculus book.

[@dr.rahulgupta7573]

Sir Is this method a Sarrus method ? DrRahul Rohtak Haryana India

[@justrandom072]

you just saved me a lot of time thank you man 😁

[@jeremycai5870]

Lol I've seen this method from a manga...

[@halfmillion9057]

how to use it on 4*4? need a quick help

[@trickypediaajoychetry]

Its a trick which consumes more time than actual method❤

[@physjim]

ok, but why?

[@azhar07464]

Wow. Didn't know about that.

[@מאוראנגלנדר-מ8ז]

Cool

[@harshchikorde9495]

Awesome

[@alfiealfie35]

Is this generalisable to higher dimensions?

[@drpeyam]

Sadly not

[@qubit01]

die gute alte jägerzaun-regel

[@raba2d723]

speak english

[@lenamaral6055]

I always preferred the method of triangles over Sarrus' rule. 😉