Functions Modeling Change: A Preparation for Calculus, 5th Edition

Try out increasingly large values of $x$. $$f(10)=\frac{1}{10}$$ $$f(100)=\frac{1}{100}$$ $$f(1000)=\frac{1}{1000}$$ You can see that as $x$ increases, $f(x)$ decreases closer and closer to zero. Therefore, the statement is true.