Answer
(a) $ x^2-9x-6$, $(-\infty,\infty)$
(b) $ \frac{x^2-5x+1}{-4x-7}$, $(-\infty,-\frac{7}{4})U(-\frac{7}{4},\infty)$
Work Step by Step
Given $f(x)=x^2-5x+1$ and $g(x)=-4x-7$, we have:
(a) $f+g=x^2-5x+1-4x-7=x^2-9x-6$ with domain $(-\infty,\infty)$
(b) $\frac{f}{g}=\frac{x^2-5x+1}{-4x-7}$ with domain $(-\infty,-\frac{7}{4})U(-\frac{7}{4},\infty)$
