- #1
perjac
- 1
- 0
Hi All,
Did my maths B exam the other day but was absolutely stumped by one question. Spent half an hour thinking about it only to give up.
Question:
A man on a kayak (K) is 3 kilometres out to sea from the nearest point, (O) of a straight beach. His destination (D) is 6 kilometres along the beach from O. The fastest he can paddle is 4 km/hr and his maximum walking speed is 5km/h. How far from O should he go ashore to reach his destination in the least possible time?
Anyways the question was alongside a whole heap of differential problems so I assume you would need to differentiate an equation, find the min SP and that should tell you the distance but I have no idea how to get to the equation or if I was even on the right track.
This was the only question I couldn't answer and it is driving me nuts.
Thanks,
Perjac
Did my maths B exam the other day but was absolutely stumped by one question. Spent half an hour thinking about it only to give up.
Question:
A man on a kayak (K) is 3 kilometres out to sea from the nearest point, (O) of a straight beach. His destination (D) is 6 kilometres along the beach from O. The fastest he can paddle is 4 km/hr and his maximum walking speed is 5km/h. How far from O should he go ashore to reach his destination in the least possible time?
Anyways the question was alongside a whole heap of differential problems so I assume you would need to differentiate an equation, find the min SP and that should tell you the distance but I have no idea how to get to the equation or if I was even on the right track.
This was the only question I couldn't answer and it is driving me nuts.
Thanks,
Perjac