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

$1+\frac{1}{e^x}$
Since $\frac{a+b}{c}=\frac{a}{c}+\frac{b}{c}$, the expression becomes $$=\frac{1}{e^x}+\frac{e^x}{e^x}=1+\frac{1}{e^x}$$