I don't understand how I'm supposed to approach this question. My initial idea was to do matrix multiplication based on S and T. However, It says that (SoT)(x) is a 2x2 matrix, but T = 3x2 and S = 2x3 so the product of T*S would be a 3x3 matrix.
Edit: I realized that doing S*T would yield a 2x2 matrix, but I'm still not sure if this is the correct method.