What real values of $x$ are not in the domain of $f(x)=\frac{1}{|x^2+3x-4|+|x^2+9x+20|}$?
For f(x) to be defined, we need both x^2 + 3x - 4 and x^2 + 9x + 20 to be nonzero, so the values of x not in the domain are -4, 1, and -5.
+193 
