Revising for my functions sac and stumbled on this question!
The cost of a taxi trip in a particular city is $4 up to and including 2km. After 2km the passenger pays an additional $2 per km. find the function f which describes this method of payment and sketch the graph of y= f(x), where x is the number of km travelled ( use a continuous model)
okay so you don't have to draw the graph for me but I have trouble with worded questions and don't get how the function is derived
Let x=number of kilometres travelled, then f(x) describes how much the person owes per kilometre.
For the first 2km, f(x)=4 (hopefully easy to see). After that, f(x) will raise $2 per kilometre, so it will be f(x)=2x+4 - BUT, we must remember to take off the 2 kilometres already travelled, giving us f(x)=2(x-2)+4=2x-4+4=2x
So, we get:
f(x)=4, 0<=x<2
f(x)=2x, x>=2
You should write this as a proper hybrid function.