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प्रश्न
In the given figure, AB is the diameter of a circle with center O and OA = 7 cm. Find the area of the shaded region.
उत्तर
Given OA = 7 cm.
Area of small circle = πr2
Where, r = `7/2`
∴ Area of circle = `22/7 xx 7/2 xx 7/2`
= `77/2` = 38.5 sq. cm.
Area of two shaded segments = Area of big semicircle - Area of Δ CBD
= `1/2 π xx 7^2 - 1/2 xx 7 xx 14`
= `1/2 xx 22/7 xx 49 - 7 xx 7`
= 11 x 7 - 7 x 7
= 77 - 49
= 28 sq. cm.
∴ Total shaded area = 38.5 + 25 = 66.5 sq.cm.
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