Question

Decide whether the function is an exponential growth or exponential decay function, and find the constant percentage rate of growth or decay. f(x) = 2229 ⋅ 0.9909x

Answer 1

f(x) = 2229 × 0.9909ˣ

We can check whether the function is a growth or a decay one by substituting values for x and see the behavior of f(x):

x = 1 → f(1) = 2208.7161
x = 2 → f(2) = 2188.616783
x = 3 → f(3) = 2168.700371
x = 4 → f(4) = 2148.965197

As we can see from the answer, f(x) is decreasing as x increasing, so f(x) is a decay function.

In the function, the constant 0.9909 represents the decay constant.