Which function is an example of exponential decay? y = 0.3(2)x y = 4(8)x y = 5(0.6)x y = 1.4(3)x

The correct answer is y=5(0.6)^x.
Exponential functions are y=ab^x
Whenever B is less than 1, that's an exponential decay and whenever B is more than one, it's an exponential growth.
I hope this helps.
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