Simple Matrix Product

1. Type: 'ALT+x' to create matrix.
2. Type: 'ALT+l' to add column.
3. Type: 'p right-arrow q right-arrow r right-arrow u right-arrow v right-arrow w right-arrow'.
4. Type: 'ALT+y' to create vector.
5. Type: 'ALT+w' to add row.
6. Type: 'x right-arrow y right-arrow z'.