Laplace expansion for computing determinants | Lecture 29 | Matrix Algebra for Engineers
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- Опубликовано: 11 сен 2024
- How to compute a determinant using the Laplace expansion (cofactor expansion, expansion by minors).
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Thank you very much for this video! I am beginning physics, and was curious about why we would subtract the j-component when solving for the cross product vector. This was a very comprehensible explanation of why.
how is he even doing the writing? is he writing on glass? Is this some editing genius. also, thank you for that explanation
He is writing on glass.
The image is flipped so the writing isn't backwards.
@@muhrizqiardi no, he isn't writing backwards, there is a mirror...
@@muhrizqiardi bruh
@@nicolasm6845 If there is a mirror then we should see his back, not his front. He is probably just writing in reverse, which is really amazing !
@@scorp6684 don't be stupid, watch this to get smarter: ruclips.net/video/eVOPDQ5KYso/видео.html
Thank you so much!!!!! I was so confused about the +, -, + logic.... Your video really helped me... Thanks again sir!!
Actually the +,-,+,- logic can be calculated using the inverse sequence
(-1)^i+j
I'm more impressed that he's doing this with all those flipped
And drawing everything with his left hand as well... stunning
Have you considered the possibility that he might have just done it normally then inverted the video..? lol
and in the dark
Thanks a lot, I got confused about the sign logic and this lecture clarified everything.
Thank you i love you, also like the way you write backwards, really clever
Thanks a lot man, I really appreciate it, you are helping me in Linear Algebra, my prof doesn't explain it in a good way, you're amazing😁
Thank you so much! I'm a Vietnamese student and will have to take calculus mid term exam tomorrow. Now I get the rule 💪💪💪💪❤❤
It's really helpful video it makes it easier to understand
I almost wanted to code it, but the complexity scales by n factorial (in the general case where there might be no zero elements). Wikipedia mentions LU decomposition and Bareiss algorithm as n^3 alternatives.
honest to god I didn't understand anything during my lecture in class today about when it came to solving 4x4 matrixes and u have helped greatly thanks!!
p.s do you write in inverse or is there some optical illusion going on with special glass where you can write normally and I also perceive it as normal writing?
thank you thank you thank you
AMAZING! !!!
Thanks
Thank god! i find this video ramdomly. because my teacher use across second roll in stead of first, and it's messup my brain because I can't understand why (- + -....) normally we use first roll (+ - +)
Thank you.
hello Sir,
what is there are no zeros in any column?
then from where we would e able to expand it?
very clear
Thank u sir
OMG! Tom Hanks is way smarter than i thought!
That's a sneaky little trick
how do you get you pen effects in your videos
ruclips.net/video/WB_CakqElQ0/видео.html
Best
thanks bro
Much easier to write and visualize columns and rows during operations
a sub1 b sub1 c sub1
a sub2 b sub2 c sub2
a sub3 b sub3 c sub3
Rather than
a b c
d e f
g h i
Quiet interesting
what if there are no zeros in the 4*4 matrix?
Then you will have 4! = 24 terms contributing to the determinant.
@@ProfJeffreyChasnov what? he means what lines you cross
i understand now what lines to cross, you cross all 3 cofactors
but you only explained for a line with one cofactor and 2 zeros....
@@marnotto8269 It works the same no matter if there are zeros or not. Zero times anything is zero
What if there isn't any Zero or any numerical value? What if there is alphabetic values like X,A,B,C?
Please reply sir.
Then it becomes algebraic.
@@ProfJeffreyChasnov but how do I solve that?
@@____myocardial_infarction____ The determinant becomes an algebraic expression with X, A, B, C, etc. I don't know what you are trying to solve.
@@____myocardial_infarction____ if you are looking for the determinant then you will wind up with det(A) = f, where f is the formula. The more coefficients you know, the more you can solve for the determinant (reduce the equation of f)
I he writing on inversely on the whiteboard, whoa
ruclips.net/video/WB_CakqElQ0/видео.html
this board is cool as fuck
Waltah....
Thanks Jeff Bezos
5-3 is 8??? WTf
it is 5 -(-3), so same as saying 5+3
I think we much thank you not you jeffrey Chasnos
this shit is not Laplace expansion
elaborate
I agree. It’s not a very rigorous explanation anyways. There’s a lot going on here that is glossed over with “you just need to remember that…”