Chapter 2.6, Problem 89E

Asymptotes of a function containing exponentials Let $f(x)=\frac{2e^x+10e^{-x}}{e^x+e^{-x}}$. Analyze $\underset{x\to 0}{\lim }f(x),\underset{x\to -\infty }{\lim }f(x)$, and $\underset{x\to \infty }{\lim }f(x)$.Then give the horizontal and vertical asymptotes of f. Plot f to verify your results.