Question 1014243
The following questions concern a circle of radius 4 cm.
a) Determine the area of the sector of a circle that subtends an angle of 2π/3 radians.
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Area of the whole circle:: pi*4^2 = 16pi
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2pi/3 is (1/3)2pi, so the area is (1/3)(16pi) = (5 1/3)pi
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b) Determine the angle at the centre of the circle that is subtended by an arc 2 cm long. Express your answer in terms of π radians accurate to 2 decimal places.

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theta (in radians) = (arc length)/(radius)
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Your Problem: 
theta = (2 cm)/r = (2cm)/(4cm) = 0.50 radian
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Cheers,
Stan H.
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