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AP® Calculus AB-BC

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Moderate

Polar Derivatives from Rectangular Equations

APCALC-AFYG4O

If $x^2+y^2=4x$, what is the value of $\cfrac{dr}{d\theta}$ when $\theta=\cfrac{2\pi}{7}$?

A

$0$

B

$2.494$

C

$3.127$

D

$-3.127$