- Find the matrix $A$ for a counterclockwise rotation of $\mathbb{R}^2$ taking the line $4x-3y=0$ to the $y$-axis.
- Find the matrix $C$ for the clockwise rotation of $\mathbb{R}^2$ taking the $y$-axis to the line $4x-3y=0$.
I've done rotations using the standard rotation matrix, but I'm not sure what the question means when it says "taking the line to the $y$-axis." I also got that the angle for the first one should be $37$ degrees, but it doesn't seem to be right. Thanks