Exercise 5.2 - Answers
1 |
(i) |
The ¬$xj rule can be applied to give: ¬$x$y[Fx®Rxy] |
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(ii) |
Neither rule can be applied. The formula does not begin with ¬" or ¬$.
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(iii) |
The ¬"xj rule can be applied. The following in a possible result:
(But one could, if one wished, add $y¬Rya to just one of the branches.) |
