P2 — Recursion — Trace, Base Case, Accumulation

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What is inside

• 1. Why this topic matters here
• 2. Exactly what gets asked
• 3. Concept notes
• 1. factorial(5) = 120
• 2. fibonacci(5) = 5, call tree and call count
• 3. Sum of first n natural numbers: n + f(n-1), n = 5 → 15
• 4. Reverse a string
• 5. power(2,5) = 32