69. Let
p(x) : x is good.
q(x) : x is too long.
r(x) : x is short enough.
The domain of discourse is the set of movies. The assertions are
∀x(p(x) → ¬q(x))
∀x(¬p(x) → ¬r(x))
p(Love Actually)
q(Love Actually ).
By universal instantiation,
p(Love Actually) → ¬q(Love Actually).
Since p(Love Actually) is true, then ¬q(Love Actually) is also true. But this contradicts,
q(Love Actually).
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