Answer
$${\text{True}}$$
Work Step by Step
$$\eqalign{
& {\text{Let }}f\left( x \right) = \arctan x \cr
& {\text{Differentiate:}} \cr
& f'\left( x \right) = \frac{d}{{dx}}\left[ {\arctan x} \right] \cr
& f'\left( x \right) = \frac{1}{{1 + {x^2}}} \cr
& {\text{Where }}m = f'\left( x \right),{\text{ then}} \cr
& m = \frac{1}{{1 + {x^2}}} \cr
& \frac{1}{{1 + {x^2}}}{\text{ is positive for all }}x,\,{\text{so }}m{\text{ is positive for all real }} \cr
& {\text{numbers }}x.{\text{ The statement is true}}{\text{.}} \cr} $$
