Incorrect Answer.


Given the predicate logic model

A = {a,b,c,d};
PM = {a,b}
QM = {(a,b), (b,b), (c,b)}
fM (a) = b, fM (b) = b, fM (c) = a, and fM (d) = c

the formula x (P(x) y Q(y,x)) is satisfied in this model if, and only if, for all values of x that satisfy P there is some value for y such that Q(y,x) holds. In this case, a and b are the only values which satisfy P. So for each one of them we have to find some value for y such that Q(y,x) holds. For x being b, we may choose a, b, or c for y to meet this requirement. However, for x being a, there is no value y such that (y,a) is in QM. Thus, this formula is not satisfy in the given model.
Back to Question.
Next Question.