Least squares examples | Alternate coordinate systems (bases) | Linear Algebra | Khan Academy

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An example using the least squares solution to an unsolvable system
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[@FoamySoaps]

This entire series got me through last semester. And if ever I need a refresher on something I come right back. Thank-you!

[@aalhorani]

Great work. But I hoped that you focused more on the graphical meaning of this method. Thanks

[@adithyavarma758]

Thank you sir

[@DuderDudre]

@jakubnage lol abstract algebra is abstract. Helpful video too

[@ruhullahdaman]

only if there was more people like you!!!

[@diegofdezz]

thanks

[@Bruno-bs5rn]

Bendito sea este hombre

[@gijsvanderklink2346]

thanks! you really helped me out. :)

[@Zebban89]

Thanks for doing these awesome videos. Thanks a million!

[@bh3302]

Thank you so much!

[@theBIGamazingShim]

i forgot i had an assignment due tonight this video helped me finish in time =D thank you so much for putting this up to help!!

[@jakubnage]

I would tend to disagree, linear algebra is quite hard and very abstract compared to the applications of calculus and where all the motivations for various ideas are explicitly mentioned when taught. Also, algebra II, III, abstract algebra, etc. are quite difficult and even more abstract.

[@nicksbologna]

Thank you soooo much I just did a math project on the Method of least squares and got a 100/100 on it because of your video

[@ethangromek3747]

Awesome, your videos really help.

[@burnfrais]

great stuff. can you please do a video on splines, clamped and natural.

[@faisalalz17]

Thanks Khan!

[@Javlini]

Sal, you said in the previous video that the equation goes || b - ax^ || not || ax^-b || like you say here. The first one made more sense to me.

[@Yash42189]

i understand u man now :D

[@Harp146]

Awesome!

[@XBARQ]

This is good

[@saranshshah7636]

if i have 2nd degree equation like y=a+b*(x)+c*(x^2) and (x,y) are (1,2)(2,4)(3,8)(4,7)(5,6)(6,9)(7,10) then what will be least square ??? find a,b,c.

[@FunOrange42]

something tells me the solution that gives the least squares would be the centroid of that triangle

[@bobsmith2889]

Ya, shouldn't it be?

[@pedrototolo8027]

off topic but I have to say I fangirled a bit when I noticed it was you @FunOrange

[@reazshafqat5504]

my question would be: why are we multiplying A(transpose) rather than A(inverse)?

[@lucasm4299]

Reaz Shafqat Because non square matrices don’t have inverses.

[@paulringab123]

The only moment you think you're smarter than khan is when you know what 15^2 is :D

[@DonVaillancourt]

So what does Khan talk about when he just chit-chats with people. He knows everything.

[@simobahada]

you're good

[@unclejam1]

better than my prof

[@Toshinben]

Not enough to restore my faith in humanity, but still really nice!

[@thepoet82]

Very good! First I thought you said you were 10 years old. :P Keep in mind that linear algebra is among the simplest college math. :)

[@alexanderchrist2531]

I LOVE YOU

[@canucksdesai]

this is fucking painful

[@DonVaillancourt]

I thought he was finished a quarter way in. No such luck.

[@sheldonchou8830]

thank you!