MATHEMATICS · Single correct · AP · AP Precalculus · Exponential and Logarithmic Functions · Exponential and Logarithmic Functions
Problem
Let f:R→(0,∞) be given by f(x)=ekx and g:(0,∞)→R be given by g(y)=ln(py), where k>0 and p>0. For which ordered pair (k,p) does each function serve as the inverse of the other, that is, g∘f=IR and f∘g=I(0,∞)?
(a) (k=2,p=1)
(b) (k=1,p=1)
(c) (k=1,p=e)
(d) (k=2,p=21)