In the figure, O is the center of the circle. The minor arc AB has a length of 4π and is 81 the circumference of the circle. If the area of the shaded region is aπ, what is the value of a ?
Q. In the figure, O is the center of the circle. The minor arc AB has a length of 4π and is 81 the circumference of the circle. If the area of the shaded region is aπ, what is the value of a ?
Calculate radius of circle: step_2: Calculate the radius of the circle.The circumference of a circle is given by the formula C=2⋅π⋅r, where r is the radius.32π=2⋅π⋅rr=2⋅π32πr=16
Calculate area of circle: step_3: Calculate the area of the circle.The area of a circle is given by the formula A=π⋅r2.A=π⋅162A=π⋅256
Calculate area of shaded region: step_4: Calculate the area of the shaded region.The shaded region is the entire circle minus the area of the sector corresponding to the minor arc AB.The sector's area is (1/8) of the circle's area since the arc is (1/8) of the circumference.Sector area = (1/8)×π×256Sector area = 32π
Subtract sector area: step_5: Subtract the sector's area from the circle's area to find the area of the shaded region.Shaded area = Circle area - Sector areaShaded area = π×256−32πShaded area = 224π
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