Question

Which of the following equations represents Exponential Decay?

y=−3x+5


y=3(0.8)x


y=−3x−5


y=0.8(3)x

Answer 1

y=3(0.8)x

Explanation:

An exponential function is a function of the form;

`y=ab^(x)`

The explanatory variable x is the exponent, a is the initial value and b the base of the exponential function.

The function is said to be an exponential decay function if the base is between 0 and 1;

0<b<1

Therefore, y=3(0.8)^x is the required function. The values of y become smaller as x increases.