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This entry develops the geometric meaning of tangent direction for complex-valued curves, explains how angles between curves may be expressed through arguments of complex numbers, and shows how this leads naturally to conformality. Particular attention is given to the condition $z'(t 0)\neq 0$, whose meaning in the complex setting is subtler than in the real case.
• Difficulty: UG-Upper
• Status: published
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A structural introduction to the natural numbers as the smallest inductive set, motivating induction and recursion.
Area: foundations
• Subarea: natural-numbers
• Difficulty: UG-Lower
• Status: published
• Updated: 2026-03-07
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Area: complex-analysis
• Subarea: regularity-rectifiability-functions-on-curves