...i'd presume this analysis would need some further analysis on the "rules of the game"
1) does the vehicle have to maintain a constant speed? a) over the flat route, and b) going up the hill?
2) w/out knowing the answer to the previous question, ...what transmission is involved and what "gear" are we "in" and what "speed" are we going?
3) does the vehicle going up hill have to stay above a minimum speed, or can it be allowed to slow down to a near stop at the crest, before being allowed to coast downhill? i.e. an uphill "coast" of sorts...
4) what is the slope of the hill? this could determine what "gear" is needed, especially if the "uphill coast" notion is deemed not allowed..
...so in summary, i don't see a way to formulate an analytical solution to this w/out more boundary conditions and specific performance characteristics for the vehicle... if so it might make a good calculus problem...
...depending on the slope of the hill, the intial speed, the characteristics of the vehicle, assume the flat route is taken at a constant initial speed, etc. ...the "uphill coast" method (i.e. start w/ initial speed at bottom of hill, and use just enough to make it to clear the crest, ...allowing speed to slowly fall off along the way..) might be feasible?...?...? but that is just my guess