Another least squares example | Alternate coordinate systems (bases) | Linear Algebra | Khan Academy

Using least squares approximation to fit a line to points

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[thepoet]

I think you made a small mistake at the end.
The final line should be:
y = (2/5)*x + (4/5)

[kickpunch]

Best video I've seen. This is how it should be taught.

[norwayte]

Excellent explanation to see least squares method in a linear algebra way instead of a calculus way. (Little writing mistake at the very end.)

[bradleyarg]

PS finding the cubic function (which has a residual squared value of 1) is -1/3x^3 + (-2.3 E -13)x^2 + (1+1/3)x + 1

[jdlopez]

Only 404 likes no way ! Thank you, Dr. Khan !

[Moonscreamcze]

thx a lot i got exam tomorow and it helped alot :-D i unfortunately have coordinates in space, but nothing i cant hadnle whit your help, thanks again i finally get the process :-D

[Priya]

This has helped me SO much for my Finals! Thanks! Keep uploading these Videos!

[Hreinn]

You might be the reason I'm gonna finish my hand in for tomorrow. Thx

[oneinabillion]

Is this a better method or the regression method for finding best fit lines

[bhatmasdal]

final exam in 1hr, another soul saved! good work khan-man!

[InsuperableMany]

Can this be done when we seek y = f(x) = c.
for some constant c, and would be the same process?

[sanskarvidyarthi]

why can't we join all the points and use the equations of the lines in the matrix?. in this case the value of the slopes and the intercepts will be different

[Jasonw]

The error come from f(1)=m+2b=2
not f(1)=m+b=2

[bradleyarg]

I remember doing this in 9th grade or was it 8th or 7th hmm... anyhow i redid on my calc in 5 min. fun thanks for the entertainment