π ≈ 3.14159
a² + b² = c²
∑ n²
√2 ≈ 1.414
∫ f(x) dx
sin²θ + cos²θ = 1
e^(iπ) + 1 = 0
lim(x→∞)
Δ = b² − 4ac
φ ≈ 1.618
y = kx + b
n! = 1·2·3·…·n
∞
π r²
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