Hi again everyone!

I have another question:

Let T : R

^{2} -> R

^{2} be the transformation that rotates each point in R

^{2} about the origin through an angle σ, with counterclockwise rotation for a positive angle. Find the standard matrix A of this transformation.

I understand that a standard matrix for a linear transformation T is the matrix relative to a standard basis, but for some reason I feel like I don't have enough information in this exercise to find it?

Thanks again for taking a look at this, you people on this forum are really the best