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the price of products may increase due to inflation and decrease due to depreciation. derek is studying the change in the price of two products, a and b, over time.
the price f(x), in dollars, of product a after x years is represented by the function below:
f(x) = 12500(0.82)x

part a: is the price of product a increasing or decreasing and by what percentage per year? justify your answer.

part b: the table below shows the price f(t), in dollars, of product b after t years:
t (number of years) 1 2 3 4
f(t) (price in dollars) 5600 3136 1756.16 983.45

which product recorded a greater percentage change in price over the previous year? justify your answer.