1. What is the difference between a matrix and a vector?
A vector is a type of matrix. A vector is a 2 X 1 matrix. A vector also can represent a translation, where the first element shows movement in the x-direction (horizontal) and the second element shows movement in the y-direction (vertical). Vectors can also be used to represent forces and position vectors can show position on the coordinate plane.
2. Why can't a 2 X 2 matrix be multiplied by a 1 X 1 matrix?
The process of multiplying two matrices can only work if the number of columns of the first matrix is equal to the number of rows of the second matrix. In this case this is not so!