After looking through my book and watching countless khan academy videos I still have no idea how to set up this problem,
Find the matrix with respect to the basis B = {(1,1,1),(1,2,-1),(2,3,1)} of the linear transformation T:R3->R3 with T(x,y,z) = (3x+y+2z, 3x+y+2z, 3x+y+2z)
Can anyone help?