6120a Discrete Mathematics And Proof For Computer Science Fix Free -

Before submitting any proof, check: ☐ Is the proof type (direct, contrapositive, contradiction, induction) clearly stated? ☐ Are all variables introduced? (“Let (x) be an arbitrary integer…”) ☐ Is each step justified by a definition, axiom, or previous step? ☐ Did I avoid starting with what I need to prove? ☐ Is the concluding sentence present? (“Therefore, (P \to Q) holds.”)

Sarah walked over, peering at his screen. "The T.A. doesn't know the half of it. You know why 6120a is so hard? Because the compiler we're using is broken. It has a bug in the induction engine." Before submitting any proof, check: ☐ Is the

| Proof Type | Strategy | Typical Mistake | Fix | |------------|----------|----------------|-----| | Direct | Assume P, derive Q | Circular reasoning | Start with given facts, use definitions | | Contrapositive | Prove ¬Q → ¬P | Confusing with contradiction | State contrapositive explicitly | | Contradiction | Assume P ∧ ¬Q, reach impossible | Not reaching a clear contradiction | End with “this contradicts X” | | Induction | Base case + inductive step | Forgetting base case or assuming what you’re proving | Write inductive hypothesis clearly | ☐ Did I avoid starting with what I need to prove

Aris looked back at the silent class.