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Question
A ladder makes an angle of 60º with the ground when placed against a wall. If the foot of the ladder is 2 m away from the wall, then the length of the ladder (in metres) is
Options
\[\frac{4}{\sqrt{3}}\]
\[4\sqrt{3}\]
\[2\sqrt{2}\]
\[4\]
Solution
Suppose AC is the ladder and BC is the distance of the foot of the ladder from the wall.
It is given that, BC = 2 m and \[\angle\]ACB = 60°.
In right ∆ABC,
\[\cos60° = \frac{BC}{AC}\]
\[ \Rightarrow \frac{1}{2} = \frac{2}{AC}\]
\[ \Rightarrow AC = 4 m\]
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