In order to gain popularity amongst high school students, Petsmart is creating a special winter promotion on toys. The function below represents the cost of toys as a function of time (measured in days after November 7th).

Piecewise function
c(t) =
2, 0<=t<=5
11-t, 5 < t <=10
7, 10<t<=14


a) What would be the best dates to buy a toy?

b) Calculate c(12) - c(5)

This is similar to one I answered yesterday.

between 0 and 5 inclusive the function = 2

between 5 exclusive and 10 inclusive

function = 11-t

between 10 exclusive and 14 inclusive

function = 7

The cheapest would be 2 so that would be Nov. 7 and 8.

c(12) used last one 7
c(5) use first one because it is inclusive there 2

7-2 = 5