Question

Let (x1, x2, x3) and (y1, y2, y3) represent the coordinates with respect to the bases
B1 = {(1,0,0),(0,1,0),(0,0,1)}, B2 = {(1,0,0),(0,1,2),(0,2,1)}.
If Q(X) = 2x21 +2x1x2 −2x2x3 +x22 +x23, find the representation of Q in terms of (y1, y2, y3).