My book gives the following definition for reduced row echelon form:(adsbygoogle = window.adsbygoogle || []).push({});

1) If a row has nonzero entries, then the first nonzero entry is 1, called the leading 1 in this row.

2) If a column contains a leading 1, then all other entries in that column are zero.

3) If a row contains a leading 1, then each row above contains a leading 1 further to the left.

1 and 3 I understand, but 2 I don't fully understand - does that mean a 'column leading 1', as in if I start at the top of a column and go down the numbers then the first nonzero entry is a 1, or does it mean that if a column contains a 1 that is a leading 1 for its row?

Thanks!

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# Reduced row echelon form question

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