Question

Which best describes the range of the function f(x) = 2(one-fourth) Superscript x after it has been reflected over the y-axis?

all real numbers
all real numbers less than 0
all real numbers greater than 0
all real numbers less than or equal to 0

Answer 1

Reflecting over the y-axis replaces x with −x: g(x)=2(1/4)^(−x)=2·4^x. Since 2·4^x>0 for all x and never equals 0, the range is (0, ∞) — all real numbers greater than 0.