Working on P.D. Magnus. forallX: an Introduction to Formal Logic (pp. 183, exercise B. 10).
I would need to find a single row in its truth table where this sentence is true:
$$(\neg R \vee C) \wedge ((C \wedge R) \to \neg R) \wedge (\neg(R \vee R) \to R)$$
However, I've not succeedded in finding one. Perhaps, am I missing something ?
That's impossible. For the third to be true, $R$ must be true. So for the first to be true as well, $C$ must be true too. But that valuation makes the second false.