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Discrete Math: Logic and Proofs

Given the conditional statement "If I am hungry, then I will eat pizza," write the converse, the inverse, and the contrapositive of the statement.

Prove that there is no way to have a lossless compression algorithm that always produces a smaller output for any given input.

Prove that a given relation RR on the set of integers Z\mathbb\Z is reflexive, symmetric, and transitive.

For all x in the domain D, the predicate P(x) is true.

There exists an X in the domain such that the predicate is true.

For all xx, there exists a yy such that xy=0x - y = 0. Is this statement true or false?

For all xx, there exists a yy such that 3xy=03x - y = 0. Is this statement true or false?

For all xx, there exists a yy such that x3y=0x - 3y = 0. Is this statement true or false?

There exists an xx and there exists a yy such that x+y=15x + y = 15. Is this statement true or false?

For all xx, x>5x > 5 implies that for all yy such that y>xy > x, y>5y > 5. Is this statement true or false?

For all xx, x>5x > 5 implies that for all yy such that y>xy > x, y>7y > 7. Is this statement true or false?

Determine if a proposition is a tautology, contradiction, or contingency using logical equivalences.

Verify the logical equivalence (pq)(pq)=p\sim (\sim p \land q) \land (p \lor q) = p using the laws of logic.

Negate the conditional statement $ ext{P} ightarrow ext{Q}$.

Negate the statement: "If it is raining, then it is cloudy."

Negate the statement: "If it is a toaster, then it is made of gold."

Negate the statement: "If wishes were horses, then beggars would ride."

Negate the statement: "If it is blue then it is not spinach."