Unfortunately, $\textsf{f2l}(1)

e 1$, but we can subtract the $C \cdot \textsf{f2l}(1)$ from both sides to get

$$ \begin{align*} \left(M^* + C \cdot \textsf{f2l}(1)\right) - C \cdot \textsf{f2l}(1) &= \left(\textsf{f2l}(1)\right) - C \cdot \textsf{f2l}(1) \\ M^* &= \boxed{(1 - C) \cdot \textsf{f2l}(1)} \end{align*} $$