Question

Enter the exponential function using t (for time) as the independent variable to model the situation. Then

find the value of the function after the given amount of time.
The value of a textbook is $63 and decreases at a rate of 14% per year for 13 years.
The exponential function that models the situation is y = 63(0.86).
After 13 years, the value of the textbook is $

Answer 1

An exponential function is given by;

f(x)=ba^x

where a is any value greater than 0,

b is the intial value

when a>1 then f(x) is defined as an exponential growth

when a<1 then f(x) is defined as an exponential decay

From the our function;

f(t)=15000(0.86)^t

a=0.86<1

b=15000

since a<1, the function will be an exponential decay.

Explanation: