a² + b² = c² e^iπ + 1 = 0 ∑ 1/n² = π²/6 √2 ∉ ℚ ∀ε>0, ∃δ>0 : |x−a|<δ ⟹ |f(x)−f(a)|<ε χ(S²) = 2 n! ~ √(2πn) (n/e)ⁿ ⊢ a = b ζ(s) = ∏ (1 − p⁻ˢ)⁻¹ ‖u + v‖ ≤ ‖u‖ + ‖v‖ det(AB) = det A · det B ∮ f dz = 2πi ∑ Res f lim (1 + 1/n)ⁿ = e ∫₀^π sin²x dx = π/2 |ℝ| > |ℕ| K ⊆ ℝⁿ compact ⟺ closed ∧ bounded gcd(a, b) = ax + by Δu = 0 d/dx ∫ₐ^x f(t) dt = f(x) ⟨u, v⟩² ≤ ⟨u, u⟩ ⟨v, v⟩ (aₙ) Cauchy ⟹ (aₙ) convergent Hom(V, W) ≅ V* ⊗ W ∫ e^−x² dx = √π ∇ × ∇f = 0 π(x) ~ x / log x