What real values of x are not in the domain of f(x)=1|x2+3x−4|+|x2+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 
