Question

Which function does NOT represent exponential decay? y=0.4(0.5)^x y=5(4)^x y=4(0.5)^x y=5(0.4)^x

Answer 1

Exponential decay is whenever the rate^2<1.  So exponential growth occurs whenever r^2>1.

In this case only y=5(4^x) is exponential growth as 4 is greater than 1

Answer 2

Answer:

The function $y=5(4)^{x}$ doesn't represent exponential decay, in fact it represents exponential growth.

Step-by-step explanation:

When we have an exponential function

$y=a(b)^{x}$

The number ''b'' is called the base of the exponential function.

If $a>1$ ⇒ The function represents an exponential growth.

If $0$ ⇒ The function represents an exponential decay.

The number ''a'' is the y-intercept of the function.

If we are looking to a function that doesn't represent exponential decay we need to pay attention to the base of the exponential.

The base of this function will be greater than 1.

The only function that satisfies this is

$y=5(4)^{x}$