The Matrix 

\begin{equation}
P = \begin{bmatrix}1 & 1 & 0 \\ 0 & 1 & 3 \\ 3 & 0 & 1
\end{bmatrix}
\end{equation} is the transition matrix from **what** basis B to the basis B' = {(1,0,0),(1,1,0),(1,1,1)} for R3?
I'm having a hard time with this one, any help is appreciated, thanks :)