An exponential decay function passes through the points and

MATHEMATICS · Subjective · AP · AP Precalculus · Exponential and Logarithmic Functions · Exponential and Logarithmic Functions

Problem

An exponential decay function passes through the points

(2,20)

and

(6,5)

. (i) Determine the base

b

. (ii) Hence find the initial value

a

in the form

f(x)=a\,b^{x}