O GRAPHS AND FUNCTIONSDomain of a rational function: Excluded values

Recall that the domain of a rational function consists of all the real numbers x except those for which the denominator is 0.
The denominator of the given rational function is:
[tex]d(x)=x^2+11x-18.[/tex]Notice that:
[tex]\begin{gathered} x^2+11x+18=x^2+2x+9x+9*2 \\ =x(x+2)+9(x+2)=(x+9)(x+2). \end{gathered}[/tex]Therefore d(x)=0 at x=-9 and x=-2, then those values are not in the domain of g.
Answer:
[tex]x=-9,-2.[/tex]