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Find the area of both the segments of a ...

Find the area of both the segments of a circle of raidus 42 cm with central angle `120^(@)`. [Given `sin 120^(@)=(sqrt(3))/2` and `sqrt(3)=1.73`]

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To find the area of both segments of a circle with a radius of 42 cm and a central angle of 120°, we can follow these steps: ### Step 1: Calculate the area of the entire circle. The formula for the area of a circle is given by: \[ \text{Area} = \pi r^2 \] Where \( r \) is the radius. Given: - \( r = 42 \, \text{cm} \) - \( \pi \approx \frac{22}{7} \) Calculating the area: \[ \text{Area} = \frac{22}{7} \times (42)^2 \] \[ = \frac{22}{7} \times 1764 \] \[ = \frac{38708}{7} \approx 5530.57 \, \text{cm}^2 \] ### Step 2: Calculate the area of the sector. The area of a sector can be calculated using the formula: \[ \text{Area of Sector} = \frac{\theta}{360} \times \text{Area of Circle} \] Where \( \theta \) is the central angle in degrees. Given: - \( \theta = 120° \) Calculating the area of the sector: \[ \text{Area of Sector} = \frac{120}{360} \times 5530.57 \] \[ = \frac{1}{3} \times 5530.57 \approx 1843.52 \, \text{cm}^2 \] ### Step 3: Calculate the area of the triangle formed by the radii and the chord. The area of the triangle can be calculated using: \[ \text{Area of Triangle} = \frac{1}{2} \times a \times b \times \sin(\theta) \] Where \( a \) and \( b \) are the lengths of the sides (both equal to the radius), and \( \theta \) is the angle between them. Given: - \( a = b = 42 \, \text{cm} \) - \( \sin(120°) = \frac{\sqrt{3}}{2} \approx 0.866 \) Calculating the area of the triangle: \[ \text{Area of Triangle} = \frac{1}{2} \times 42 \times 42 \times \frac{\sqrt{3}}{2} \] \[ = \frac{1}{2} \times 1764 \times 0.866 \approx 762.93 \, \text{cm}^2 \] ### Step 4: Calculate the area of the smaller segment. The area of the smaller segment is given by: \[ \text{Area of Smaller Segment} = \text{Area of Sector} - \text{Area of Triangle} \] Calculating: \[ \text{Area of Smaller Segment} = 1843.52 - 762.93 \approx 1080.59 \, \text{cm}^2 \] ### Step 5: Calculate the area of the larger segment. The area of the larger segment can be found by subtracting the area of the smaller segment from the area of the sector: \[ \text{Area of Larger Segment} = \text{Area of Circle} - \text{Area of Sector} - \text{Area of Triangle} \] Calculating: \[ \text{Area of Larger Segment} = 5530.57 - 1843.52 - 762.93 \approx 3924.12 \, \text{cm}^2 \] ### Final Results: - Area of the smaller segment: \( 1080.59 \, \text{cm}^2 \) - Area of the larger segment: \( 3924.12 \, \text{cm}^2 \)

To find the area of both segments of a circle with a radius of 42 cm and a central angle of 120°, we can follow these steps: ### Step 1: Calculate the area of the entire circle. The formula for the area of a circle is given by: \[ \text{Area} = \pi r^2 \] Where \( r \) is the radius. ...
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