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# Find All Critical Numbers

APCALC-UZYLGB

Find all of the critical numbers for $f(x)=3\sin{x}-3x\cos{x}$.

A

$x=2k\pi$ for any integer $k$

B

$x = (2k+1)\pi$ for any integer $k$

C

$x=\cfrac {2k+1}{2}\pi$ for any integer $k$

D

$x=k\pi$ for any integer $k$