### Home > APCALC > Chapter 8 > Lesson 8.3.1 > Problem8-103

8-103.

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

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

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

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

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

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

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.