The man is in boat from the nearest point on the coast.
He is to go to a point , located
down the coast and
inland.
The man can row at speed of and walk at
.
Observe the diagram,
\ and
.
.
Here the time is considered for both the man can row in water and walking time.
\The time taken by man to reach the point is
.
.
Apply derivative on each side with respect to .
The man can reach the point in minimum time when
.
.
Let .
Apply derivative on each side with respect to .
.
Since and
, the solution is in the interval
.
Newtons approximation method formula :
.
Substitute and
.
.
Perform Newton approximation for .
The calculations for si iterations are shown in the table.
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Observe the table:
\The minimum time approximation is .
The minimum time approximation is .