Solutions to Homework #9, Problems 23-29

At least one of a, c, and e is a cube ... we’re not going to go twice and that one cannot walk while driving or vice versa – to say that “We can walk to the movie or we can drive, or we can do both.” is a self contradictory statement. ... ( E follows by modus ponens. Now, since we know D ( E and (E, D follows by the definition of ... ................
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