Null space 2: Calculating the null space of a matrix | Linear Algebra | Khan Academy

Calculating the null space of a matrix

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[jugheadsp]

8:30 ... should be 3 X4 rather than 3 X2.

great video :D really helpful

[Crazy]

besides for a errors @5:27 and @5:55, these is very helpful! much better than my 2 hour lectures

[bencolleymusic]

It's okay Sal, you're not the only one whose mind wanders in Linear Algebra :D
Great help as always.

[Kerendipitous]

"zero minus zero is zero!" he says it with such shock.

[tauceti]

10:52 Span of Nullspace - the vectors broken-up in addition
Form:
N(A) = x_1 [v1..] + x_2 [v2..]
N(A) = ((RREF(A))

[Nachtmusiks]

He makes everything so easy to understand. It's almost a waste to go to class.

[CrimsonCorn]

My math lecturer just regurgitates the textbook into power points. This helps a great deal.
Thanks!!!

[nighttfallNZ]

Thanks mate, you're a legend. Easy to understand and follow! Keep up the good work!

[sidaksingh]

My Math professor who has a degree from University of Chicago couldn't explain as well as you can!!! I vote you for Professor of the year!!!

[Rovshenification]

This is the Method 1. We can use Method 2 which is called Special Solution. We can apply this method 2 after rref(A), then we must determine our pivots column and free variables. We have to take free variable as 1 and zero. (For example we have 2 f.v x1 and x2. firstly we must take x1=1 and x2=0 and calculate our combination, then x1=0, x2=1 and again calculate).

Thanks for this lesson :)

[ThingsFree-ThingsFree]

Thank you much, you are an amazing teacher and i would love if you be my teacher for all the courses i take.
I see you better than a loooot of teachers with PHs.

[Brenstar]

Never been happier in my life to identify a span! Thanks Khan!

[SciHeartJourney]

I caught your minor mistake because you've trained us so well over the years. I had thought I was going crazy, but then you caught it yourself. 😄 Thank you for all of your excellent videos, like this one.

[BabyXGlitz]

such an effective delivery of a material, magical

[Tobyonekenoby]

Thank you so much! I have had a hard time figuring out the null space and thanks to you i am now able to solve it :)

[dzhaon]

Mistakes happen, what this video aims for is to teach the concept of Null spaces. I personally think it has done a great job on that.

[abubakarqasim]

JazakAllalh Khair for all that you've done, going for my exam now after Jummah for Linear Algebra.

[imRyRy]

The second one: It's the set of all vectors 'x' for which Ax=0.

Another way to write it out:

N(A) = {x ∈ R^n | Ax = 0}

"x is an element of the n dimensional space of real numbers, that satisfies Ax=0 for some given matrix A"

[giaotran]

oh my god after three weeks and one failed midterm, I finally got it. Thank you.

[cmburnsie]

Great video, as always!

Just a question: When you reduced the third row (with the second) to 0, 1, 2, 3 - shouldn't it be 0, -1, -2, -3 ?

In the end, it will be a 0, 0, 0, 0-row anyway, but just to easy my mind - am I wrong? (it was about 5 years since I took a math class, so I'm probably wrong)

/John, Sweden