Exercise 5

Describe geometric effect that the following matrices have on $\real^2$:

1. $A = \left[\begin{array}{rr} 2 & 0 \\ 0 & 2 \\ \end{array}\right]$

2. $A = \left[\begin{array}{rr} 4 & 2 \\ 0 & 4 \\ \end{array}\right]$

3. $A = \left[\begin{array}{rr} 3 & -6 \\ 6 & 3 \\ \end{array}\right]$

4. $A = \left[\begin{array}{rr} 4 & 0 \\ 0 & -2 \\ \end{array}\right]$

5. $A = \left[\begin{array}{rr} 1 & 3 \\ 3 & 1 \\ \end{array}\right]$