Official Correct Answer: B. ### Core Concept & Formula
To determine the range of a rational function \( f(x) = \frac{p(x)}{q(x)} \), set \( y = f(x) \) and solve for \( x \) in terms of \( y \). The function will have real values if the discriminant of the resulting quadratic equation is non-negative. The discriminant \( D \) of a quadratic equation \( ax^2 + bx + c = 0 \) is given by \( D = b^2
Answer and solution
Answer:B) (−∞,81]∪[21,∞)
📌Core Concept & Formula
To determine the range of a rational function f(x)=q(x)p(x),sety = f(x)andsolveforxintermsofy.Thefunctionwillhaverealvaluesifthediscriminantoftheresultingquadraticequationisnon−negative.ThediscriminantDofaquadraticequationax^2 + bx + c = 0$ is given by \( D = b^2