I want to prove the following statement.
If a+2>0, then a>-2.
What does "assume by contradiction that a<=-2" mean?
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Sign up to join this communityI want to prove the following statement.
If a+2>0, then a>-2.
What does "assume by contradiction that a<=-2" mean?
A proof by contradiction depends on the law of the excluded middle. The law of the excluded middle, in this situation, claims that either a > -2 is true OR else a <= -2 is true.
Thus, an "assumption by contradiction" is technically a theorem in propositional logic that is not susceptible of proof or disproof.