# Calculus

Find the rate of change of the circumference of a circle with respect to the area when the area is 4π square feet.

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1. C = 2πr
A = πr^2
C = 2π√(A/π) = 2√π √A
dC/dA = 2√π * 1/(2√A) = √(π/A)

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oobleck

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