How to calculate a kernel in matlab

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

Im trying to replicate this matrix in MATLAB but I don't receive the same solution

EDIT :

I have this matrix.

A = [1 1 1 1;1 2 3 4; 4 3 2 1]

According to the video the kernel of this matrix is:

A = [1 -2  1 0] B= [2 -3 0 1]

but in MATLAB I receive a different result

null(A)

ans =

      0.0236    0.5472
     -0.4393   -0.7120
      0.8079   -0.2176
     -0.3921    0.3824

I'm doing something wrong?

[KSSV]

Can you elaborate your question? Do you think the people who answer will go through the complete video and get solution for you? You explain your problem in brief, you will get your solution soon...:)

[Jorge Tirado]

OK I edit the description thanks

[AYOUB]

Use this

null(A,'r')

Result:

1 2

-2 -3

1 0

0 1

Answer 1

[OM]

Jorge, you should probably execute as follows: null(A, 'r')

MATLAB is giving you an orthonormal basis and what you are looking for is sometimes called a "rational" basis.

Answer 2

[the cyclist]

Quick web searching (despite utter ignorance on my part) suggests that you might want

rref(A)

rather than

null(A)

[Jorge Tirado]

But how I can obtain the Ker ?

[Limanan Nursalim]

Kernel/nullspace is obtained by using the

null(A)

as written.

To find the image/range, you can use

rref(A')