Answer
(a) $ x^2-9x-6$ , $(-\infty,\infty)$.
(b) $ \frac{x^2-5x+1}{-4x-7}$, $\{x|x\ne-\frac{7}{4} \}$.
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 $\{x|x\ne-\frac{7}{4} \}$.
