For clarity, please enclose the denominator in parentheses: (x^2-3x-4).
This is a rational function whose DOMAIN is "all real numbers for which the denominator is not zero." Purposely set the denom. equal to zero and solve for x. Answers: {4,-1}. Thus, the domain is "the set of all real numbers not equal to 4 or -1." This can be written as (-infinity,-1) U (-1,4) U (4, infinity).
RANGE: the set of all possible values of this rational function. Please note that if we let x grow larger and larger, the value of this function approaches, but never equals, 1. Thus, the RANGE is (-infinity, 1) U (1, infinity).
