Solution
= Solution
In $T(z)\partial X(w)$, a single Wick contraction can be made with either factor in $T$. Using the two-point function and expanding the remaining field around $w$ gives
$$
T(z)\partial X(w)
\sim\frac{\partial X(w)}{(z-w)^2}
+\frac{\partial^2X(w)}{z-w}.
$$
This <operator product expansion> says that $\partial X$ is a holomorphic <primary operator> of conformal weight $(1,0)$.