Question

Which of the following could be an example of a function with a range (-∞,a] and a domain [b, ∞) where a > 0 and b > 0?

A. ƒ(x)= √(x-a)+b
B. ƒ(x)=-√(x-b)+a
C. ƒ(x)=-3√(x+a)-b
D. ƒ(x)=3√(x+b)-a

Answer 1

For option a: domain is [a, ∞), range is [b, ∞)
For option b: domain is [b, ∞), range is (-∞, a]
For option c: domain is [-a, ∞), range is (-∞, -b]
For option d: domain is [-b, ∞), range is [-a, ∞)

Hence the correct answer is option b.