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प्रश्न
An arc of length 15 cm subtends an angle of 45° at the centre of a circle. Find in terms of 𝜋, radius of the circle.
उत्तर
Length of arc = 15cm
𝜃 = angle subtended at centre = 45°
Let radius = r cm
arc length = `theta/360^@`× 2𝜋𝑟
=`45^@/360^@`× 2𝜋𝑟
`45/360`× 2𝜋𝑟 = 15
𝑟 =`(15×360)/(45×2pi)=60/pi`cms
𝑅𝑎𝑑𝑖𝑢𝑠 =`60/pi`cms
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