+1926 Find the real numbers x that are not in the domain of
f(x)=1(x2−6x+8)−(x2+x−6).
+189 f(x) is a rational function, so an x-value that could realistically not be in the domain occurs when the denominator equals 0.
(x2−6x+8)−(x2+x−6)=0x2−6x+8−x2−x+6=0−7x+14=0−7x=−14x=−2
The value of x = -2 causes the denominator to be 0, x = -2 is the only x-value not in the domain of this function!
