Chapter 1 - Linear Equations in Linear Algebra - 1.9 Exercises - Page 79: 24

a. not 1 to 1 b. T maps R^{3} onto R^{2}

a. 3 columns and 2 dimensions mean the columns of a are linearly independent. So it is not 1 to 1 b. A has a pivot in each row, so the columns span R^{2} So T maps R^{3} onto R^{2}