He was calculating in his head.

There was a long queue in front of the movie theater.

People were forming a line from early morning to buy concert tickets.

He solved complex mathematical problems using his new calculator.

A Hermitian matrix refers to a matrix that is equal to its complex conjugate transpose.

In linear algebra, triangular matrices play a very important role.

In linear algebra, symmetric matrices play a very important role.

A skew-symmetric matrix has the characteristic that its transpose matrix is the inverse of the original matrix.

I learned an algorithm to calculate the inverse matrix.

This square matrix has the same number of rows and columns.