Rows , columns , or a block of rows or columns can be deleted from a matrix.
To delete (a block of) rows or columns
To add rows or columns of entries
Tip In the special case of a vector represented as an n×1 or 1×n matrix, you can lengthen the vector by placing the insertion point in the last input box and pressing ENTER. You can shorten a vector by placing the insertion point in the last input box and pressing BACKSPACE. You can start with a display box, or the input boxes that appear with the fraction, radical, or bracket buttons, and make the same kinds of changes.
To change the alignment of entries
You can replace a rectangular block in an existing matrix using Fill Matrix.
To change a matrix with Fill Matrix
The selected region of the matrix is filled with the entries that you chose.
The lower-right corner is replaced by the 2×2 zero matrix. No new matrix is created.
You can delete a block of entries in a matrix by selecting a rectangular portion of the matrix with the mouse, and pressing DEL.