Find the standard matrix of the linear transformation T. T: :R 2 rightarrow :R 2 rotates points (about the origin) through 7/4 pi radians (with counterclockwise rotation for a positive angle). Solution For counter clock rotation thro ? matrix = { { -cos(?), sin(?) }, { sin(?), cos(?) } } here ? = 315 Setting ?=315 gives { {-0.707, -0.707}, { -0.707, 0.707 } } so answer is option D.