Compute the standard matrix representing each of the following linear transformations from R2 to R2:
(a) L is the linear transformation that doubles the length of x and then reflects it about the x2 axis.
A=
(b) L is the linear transformation that rotates x 180 degrees counterclockwise and then reflects it across the x1 axis.
A=
(c) L is the linear transformation that reflects x across the line x2=x1 and then rotates it 45 degrees counterclockwise
A=