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प्रश्न
The area of a semicircle of radius 4r is ______.
विकल्प
8πr2
4πr2
12πr2
2πr2
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उत्तर
The area of a semicircle of radius 4r is `bb(underline(8 πr^2))`.
Explanation:
Given, radius of semi-circle = 4r
∵ Area of semi-circle = `1/2 xx πr^2`
= `1/2 xx π xx (4r)^2`
= `16/2`πr2
= 8πr2
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