I want to slove this exercise like this video is german but you can see the steps: https://www.youtube.com/watch?v=fe0mx5SlLfI I have problem with last steps. Its impossibil the z3=6+4j/-2 or its true then I must continue but I don't now how.

Question

anonymous · Answer

attachment

anonymous · Answer

exercise on jpg

mathmate · Answer

Look for an error on the last line in the last matrix.
II-III does not give what you expected.
Should be [0,2,2]=6

mathmate · Answer

x1,x2 and x3 are all real and $\in$ Z.

anonymous · Answer

ok I look

anonymous · Answer

in matrix I must have three 0. the 2 in middle I cant understand it

anonymous · Answer

hello u neednt to look here but when I can only one question about it.

mathmate · Answer

If you solve by Gaussian elimination, you need zeroes in the lower triangular matrix, that's why you need three zeroes, as you have tried to do.
If you have not solved the problem yet, let me know.

anonymous · Answer

$$\begin{array}{rrr|rrr} 2 & -1 & 0 & 1 & 0 & 0\ 1 & 2 & -2 & 0 & 1 & 0\ 0 & -1 & 1 & 0 & 0 & 1 \end{array}$$