CPM Homework Help : APCALC Problem 8-103

Multiple Choice: $\frac { d } { d x } [ \operatorname { arccos } ( 3 x ) ] =$

$\frac { 3 } { \sqrt { 1 - x ^ { 2 } } }$

$\frac { - 1 } { 3 \operatorname { sin } ( 3 x ) }$

$\frac { 3 } { \sqrt { 1 - 3 x ^ { 2 } } }$

$\frac{3}{\sqrt{1-9x^2}}$

$\frac{-3}{\sqrt{9x^2-1}}$

Hint:

Without jumping straight to the Chain Rule, you can figure this out. Visualize what the $3$ does to the graph of $y = \arccos(x)$ . It will do the same thing to the slope function.