A fence(3m tall) parallel to the wall of a building and 1m from the building.What is the length of the shortest ladder that can be extend from the ground over the fence to the building wall?
1 Answer
Sep 16, 2015
the minimum length of ladder is 5.406m
Explanation:
answer is very simple . the length of the ladder which is to be caluclated must be minimum .
so the length of the ladder = 3*cosec (x)+sec(x)
applying derrivation on both sides gives the minimum length of ladder required
0= -3cosec(x)cot(x)+sec(x)tan(x)
that implies
x=55.7 degrees
the minimumlength of the ladder is 3cosec(55.7)+sec(55.7) (in degrees)
the minimum length of the ladder is 5.406m