A boat has to cross a river. It crosses the river by making an angle of 60 \degree with the bank of the river due to the stream of the river and

travels a distance of 600m to reach the another side of the river. What is the width of the river?
travels a distance of 600m to reach the another side of the river. What is the width of the river?
Step 2: Analyse the given question. Draw a figure from the given information.
GIVEN: Angle between the bank of the river and way of the boat \angle CAB = 60\degree.
Traveled distance AC = 600 m
Determine the width of the river AB = ?
Step 2: Select the appropriate trigonometric ratio.
EXAMPLE: We need to find the width of the river(adjacent side)
So, take \cos\ A=\frac{adjacent}{hypotenuse}
\cos60\degree=\frac{AB}{AC}=\frac{AB}{600}
\frac{1}{2}=\frac{AB}{600} (Since \cos 60\degree = \frac{1}{2})
AB=\frac{600}{2})
AB = 300
The width of the river = 300 m