Among the given statements below (a) \( \neg p \vee (\neg p \vee q) \) (b) \( \neg q \wedge (\neg p \vee \neg q) \) (c) \( (\neg p \vee \neg q) \wedge (p \vee \neg q) \) (d) \( (\neg p \vee \neg q) \vee (p \vee \neg q) \) .............. is a tautology.
The integrating factor of the differential equation \(\sin y \frac{dy}{dx} = \cos y (1 - x \cos y)\) is