\(\text{If $f(x)=\frac{x+4}{x^2+ax+b}$, and $f(x)$ has two vertical asymptotes at $x=1$ and $x=-2$, find the sum of $a$ and $b$. }\)
Thanks in advance!
x + 4
f(x) = ___________
x^2 + ax + b
If we have vertical asymptotes at x = 1 and x = -2 then the denominator is ( x - 1) ( x + 2)
So.....the denominator becomes x^2 - 1x + 2x - 2 = x^2 + 1x - 2
So a = 1 and b = - 2
And their sum is - 1
