Simon travels north and south from Main Station. The distance, in km, of the train from
Main Station is modeled by the function π(π‘) = π‘
3 β 9π‘
2 + 6π‘, where North is positive and
South is negative. Time elapsed after the start of a shift, in hours, is represented by t,
where π‘ β [0,12]. If the shift starts at noon, determine at which time(s) the train is more
than 16 km south of Main Station.
I don't get where to start. Please help!