Question

From the top of a light house 60 metre high with its base at the sea level the angle of depression of a boat is 15^o. The distance of the boat from the foot of the light house is

• A. $\left( \frac { \sqrt { 3 } - 1 } { \sqrt { 3 } + 1 } \right) 60$metre
• B. $\left( \frac { \sqrt { 3 } + 1 } { \sqrt { 3 } - 1 } \right) 60$metre
• C. $\left( \frac { \sqrt { 3 } + 1 } { \sqrt { 3 } - 1 } \right)$metre
• D. None of these

Answer 1

Answer: (B)

$\left( \frac { \sqrt { 3 } + 1 } { \sqrt { 3 } - 1 } \right) 60$metre

Answer 2

Required distance = $60 \cot 15 ^ { \circ }$

$= 60 \left[ \frac { \sqrt { 3 } + 1 } { \sqrt { 3 } - 1 } \right]$ metre

$60$