Triangular matrix (Upper and Lower triangular matrix) - Practice Questions & MCQ

Triangular matrix: A square matrix whose all elements above or below principal diagonal are zero is called a Triangular matrix.

A triangular matrix is further classified into two types:

1.  Upper triangular matrix
2.  Lower triangular matrix

Upper triangular matrix: A square matrix whose all elements below principal diagonal are zero is called upper triangular matrix.

Or   is said to be upper triangular if  when i > j.

E.g., 

Lower triangular matrix: A square matrix whose all elements above principal diagonal is zero is called a lower triangular matrix.

Or  is said to be upper triangular if   when i < j.

Eg.