Template for Problem Solutions (With Guiding Questions)
Problem Statement
Q: What exactly is being asked?- Clearly restate the problem.
Example: “Prove √2 cannot be written as a fraction of two integers.”
- Clearly restate the problem.
Initial Intuition
Q: What’s your first instinct or assumption?- Describe patterns, guesses, or starting assumptions.
Example: “Assume √2 is rational. If this leads to a contradiction, it must be irrational.”
- Describe patterns, guesses, or starting assumptions.
Step-by-Step Solution
Q: How can you break this down logically?- Write the solution flow.
Example: - Let √2 = a/b (simplified fraction).
- Square: 2b² = a² ⇒ a is even.
- Substitute a = 2k ⇒ b² = 2k² ⇒ b is even. Contradiction. Note that this step is quite involved, so there will be another post on this.
- Write the solution flow.
Key Insights
Q: What made the solution work?- Highlight pivotal ideas or techniques.
Example: - Proof by contradiction.
- Divisibility/parity arguments.
- Highlight pivotal ideas or techniques.
Fragile Assumptions
Q: What could break this solution?- Identify implicit assumptions or overlooked edge cases.
Example: - Not ensuring a/b is in lowest terms.
- Missing the parity chain (a even ⇒ b even).
- Identify implicit assumptions or overlooked edge cases.
Alternative Paths
Q: Could a different method work?- Suggest other approaches.
Example: - Geometric infinite descent (e.g., shrinking right triangles).
- Suggest other approaches.
Generalizations
Q: Can this apply to similar problems?- Extend the core idea to broader cases.
Example: - Replace 2 with any prime p to prove √p is irrational.
- Extend the core idea to broader cases.
Connections
Q: Where else have you seen this pattern?- Link to analogous problems or domains.
Example: - Similar contradiction logic applies to proving log₂3 is irrational.
- Link to analogous problems or domains.
Reflection
Q: What would you do differently next time?- Critique your process and identify improvements.
Example: - “Next time, I’d check if the Rational Root Theorem could shortcut the proof.”
- Critique your process and identify improvements.
Example Flow with Questions (√2 Proof):
- Key Insights: Q: What unlocked the solution?
- Contradiction + parity analysis.
- Fragile Assumptions: Q: What nearly broke the proof?
- Forgetting to reduce a/b initially.
- Connections: Q: Similar problems?
- Irrationality of √3, e, or sums like √2 + √3.
- Reflection: Q: What’s your takeaway?
- “Contradiction is powerful for impossibility proofs—look for structural mismatches.”
Why This Works: Questions force active engagement, surface hidden assumptions, and link ideas across domains. The template becomes a dialogue with your reasoning.
Final template (concise version):
- Problem Statement
- Initial Intuition
- Potential Paths
- Step-by-Step Solution
- Key Insights
- Fragile Assumptions
- Alternative Paths
- Generalizations
- Connections
- Reflection