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2 votes
Are all upper triangular matricies and lower triangular matrices

always invertible?

If so, I'd like to know the reason!
If not, what are special cases that are invertible?

Thank you in advance.

User Imiric
by
8.3k points

2 Answers

2 votes

Answer:

No, not all upper triangular matrices and lower triangular matrices are always invertible.

Explanation:

I did the test

Hope this helps :)

User Ilias
by
8.3k points
3 votes

Answer:

No, not all upper triangular matrices and lower triangular matrices are always invertible. A triangular matrix (lower or upper) is invertible if and only if all entries of the main diagonal are non-zero.

Explanation:

User Dana Cartwright
by
8.7k points