Answer
The students will enjoy graphing the cosine and secant functions because the graphs of $\cos{x}$ and $\cos{(-x)}$, as well as the graphs of $\sec{x}$ and $\sec{(-x)}$, are the same.
Work Step by Step
Students who seem to ignore negative signs will enjoy graphing functions involving cosine and secant functions because the graphs of $\cos{x}$ and $\cos{(-x)}$ are identical or the same, while the graphs of $\sec{x}$ and $\sec{(-x)}$ are also identical or the same.